Hastings' Dictionary of the New Testament 
Heart —In the NT ‘heart’ (καρδία) is the word most commonly used to denote the inner nature of man, the secret core of his being, where the springs of his intellectual and moral activity reside. In this, its general significance, it is the equivalent of the Hebrew term לֵב or לֵבָב in the OT. Originally employed to designate the bodily organ which is the centre of the animal life, it came by a natural process of thought to be applied to the invisible centre of the thinking and responsible life. In this sense it occurs with notable frequency in the Gospels; but there, like the corresponding word in the OT, whilst always referring to man’s interior nature, it is used in a variety of applications, according to the particular functions or aspects of that nature which are meant to be expressed. This is the ease also in the other NT writings.
i. Shades of meaning in the Gospels.—Heart in the Gospels is variously regarded—
1 . As the faculty of thought, intelligence, and memory .—Persons are spoken of as pondering ( Luke 2:19), musing ( Luke 3:15), reasoning ( Luke 5:22), having thoughts arising ( Matthew 9:4, Luke 9:47; Luke 24:38) in their heart; understanding or not with their heart ( Matthew 13:15, Mark 6:52; Mark 8:17); keeping, or laying up, things said or done, in their heart ( Luke 1:56; Luke 2:51).
2 . As the seat of the affections, emotions, and passions :— e.g. of love for God ( Matthew 22:37, Luke 10:27), for earthly or heavenly treasure ( Matthew 6:19-21); of joy ( John 16:22, Luke 24:32); of sorrow ( John 14:1; John 16:8); of forgivingness ( Matthew 18:35), purity ( Matthew 5:8), humility ( Matthew 11:29); of good or evil dispositions ( Matthew 12:34-35), perverse inclination ( Matthew 5:28, Matthew 24:48), luxurious tastes and desires ( Luke 21:34).
3 . As the source of purpose and volition .—The disciples are enjoined to settle in their hearts not to meditate what they shall say ( Luke 21:14); the fell design of Judas was put into his heart by Satan ( John 13:2); the adulterous act is virtually done in the intention of the heart ( Matthew 5:28).
4 . As the organ of moral discernment and religious belief, i.e. of conscience and faith .—Reproofs are given for the hardness of heart which prevents the reception of the truth ( Matthew 19:8, Mark 3:5; Mark 16:14), and for slowness of heart to believe ( Luke 24:25); there is an exhortation not to doubt in the heart, but believe ( Mark 11:23); and the pure in heart have the promise of Divine illumination ( Matthew 5:8).
In one passage only we find the phrase ‘the heart of the earth’ ( Matthew 12:40).
ii. Christ’s emphasis on the heart.—The superlative importance which Christ attached to the heart and its right condition was one of the pre-eminent characteristics of His teaching. He possessed an unrivalled insight into the workings of the heart ( John 2:24-25), and could read what was going on there with a penetration and accuracy often startling ( Matthew 9:4; Matthew 12:25; Matthew 22:18, Mark 2:8, Luke 9:47). But His unique peculiarity was the seriousness and persistency with which He dealt with the heart, and laboured for its purification as the one concern vital to the well-being of men. To the heart He always appealed, and on its deepest instincts He sought to bring His influence to bear; and although in many of His utterances the heart is not expressly named, it is still obvious that He had it directly in view. This was the ‘inwardness’ which constituted His great secret. The main points on which He insisted were:
1 . The heart as the source of all the good or the evil in men’s lives .—He dwelt on this with special earnestness— e.g. in His reply to the tradition-bound objectors, ‘Out of the heart proceed evil thoughts, murders, adulteries,’ etc., ‘the things which defile a man’ ( Matthew 15:19 f.); and in that suggestive saying, ‘A good man out of the good treasure of his heart bringeth forth that which is good, and an evil man out of the evil treasure of his heart bringeth forth that which is evil’ ( Luke 6:45); and the idea is to be found running through all His teaching.
2 . The dispositions and motives of the heart as determining the religious value of actions .—Jesus unfailingly taught that the test of a man’s worth before God was not the outward propriety of his conduct, but the heart-inclinations and purposes by which he was swayed ( Luke 16:15). Even a correctly decorous Pharisee like Simon did not stand so high in the Divine estimation as the frail woman who had erred sadly, because, while he was proud and self-satisfied in his moral respectability, she, amid all her failings, was melted into heartfelt penitence and gratitude ( Luke 7:36-39). A man’s conduct may be free from all formal commission of impurity, but if he lust after a woman in his heart, the stain of impurity is already incurred ( Matthew 5:28). Many things outwardly right and proper were done by the religionists of His day—seasons of prayer duly observed, alms given, etc.—which yet He pronounced to be of little moral value because done from a false motive, the desire for social credit, ‘to be seen of men’ ( Matthew 6:2; Matthew 6:5). On the other hand, humble and obscure actions, like the widow’s offering and the publican’s supplication, He declared to be of inestimable worth in the eye of Heaven, by reason of the genuine heart-feeling from which they sprang ( Mark 12:41-44, Luke 18:13-14). And in the great Judgment-picture ( Matthew 25:31-46), He made it clear that it is the frank, unaffected generosity of the heart, finding expression in deeds of simple dutifulness, that ranks high in the Father’s sight and secures the reward of immortal blessedness. Always and everywhere He pierced below surface appearances, and demanded inner rectitude as the criterion of worth.
3 . The regeneration of the heart as essential both to a right relation to God and to true happiness .—The repentance Jesus preached meant a change of heart ( Matthew 4:17; Matthew 9:13, Luke 13:3); the conversion He urged as a necessity was a turning of the heart to God as the source of life and grace ( Matthew 13:15, Mark 4:12, John 12:40), a restoration of the childlike spirit ( Matthew 18:3), a new birth within, apart from which it is impossible to enjoy the blessings of the heavenly Kingdom ( John 3:3-7).
iii. Evils counteracted by Christ’s teaching.—Of these, four at least may be specially noted:
1 . A pretentious ecclesiasticism .—Men’s minds were drawn away from dependence on the mere institutional aspects of religion, and confronted with the absolute necessity of internal righteousness. When orthodox Jews took a stand on their connexion with an ancient religious organization with its high covenanted privileges, and boasted of being children of Abraham, Christ flatly challenged their right to such a title, because of the vile purposes they cherished in their hearts, which proved that they did not possess Abraham’s spirit ( John 8:39). He avowed that a scorned publican like Zacchaeus, who was outside the pale of ecclesiastical recognition, was more truly a son of Abraham, in virtue of the higher dispositions which had been stirred in his heart, and which placed him in the line of moral and spiritual descent ( Luke 19:9). Again, in face of the arrogant presumption that restricted Divine blessing and salvation to those within the bounds of Judaism and its religious system, He held up the kind services of a generous heart as sufficient to raise even a Samaritan to a level of equal worth before God ( Luke 10:30-37).
2 . An external ceremonialism .—Jesus attacked, sometimes with fiery indignation, the superficiality of that righteousness which was based on a punctilious attention to certain prescribed observances,—the tithing of mint and cummin, when justice, mercy, and the faith of the heart were neglected ( Matthew 23:23, Luke 11:42); the fastings which had no genuine penitence behind them ( Matthew 6:17-18); the careful washing of hands, while the heart was inwardly defiled ( Matthew 15:2-3). It was His dominant idea that on the disposition of the heart the spiritual value of worship depends ( John 4:24), and He had strong warnings to utter against the offerings at the altar when sinister feelings were nursed within ( Matthew 5:23), and the ascription of honour to God with the lips while the heart was far from Him ( Matthew 15:8). With scathing rebukes He exposed the pretensions of those who claimed peculiar sanctity on the ground of their ceremonial scrupulousness, characterizing them as whited sepulchres, outwardly fair, but inwardly full of uncleanness ( Matthew 23:27). Thus He represented all external acts of righteousness which do not spring out of an upright, pious heart as a mere hypocritical show, and not real righteousness ( Matthew 6:1-6).
3 . A legalistic moralism .—In view of the fact that the great spiritual ideas inculcated by the prophets had been hardened into fixed laws and rules, in formal obedience to which righteousness was made to consist, Christ’s endeavour to recall men to the supreme importance of inner motive was calculated to exert a powerful effect. The confidence which many had in their moral respectability was necessarily shaken when they found themselves forced to look within, and judge themselves by something higher than a legal standard; as, e.g. , in the case of the young man who had great possessions, and whose conduct outwardly was without reproach ( Matthew 19:16-22). And there can be little doubt that the uneasiness and irritation created among the professedly religious classes by Christ’s teaching was largely due to the consciousness it wakened in them of the insufficiency of the grounds on which their claim to righteousness was based. In the light of the stress He laid on the hidden springs of action in the heart, their moral regularity of life, founded on mere conformity to laws and rules, was bound to appear unsatisfactory and poor.
4 . A self-sufficient secularism .—Such teaching, setting the renewed dispositions of the heart far above the riches and honours of the world in value, supplied a potent counteractive to the proud security and self-assumption which prosperous worldliness is apt to beget. It forced home the sense of something wanting within, even when the outward fortunes were flourishing. The parable of the Rich Fool is a vivid picture of the real poverty of the man who trusts in his worldly success and is not rich in the things that belong to the inner life ( Luke 12:16-21); while in the parable of the Rich Man and Lazarus there is another picture, fitted to break down the self-confidence of the prosperous, showing that the day will come when conditions may be reversed, and when heart-qualities alone will determine the status and happiness of men ( Luke 16:19-31).
iv. The revivifying effect on religion.—By His insistence on the heart as the vital element in righteousness, Christ transformed the whole character of religion. He made it (1) living ,—not mechanical, a matter of prescribed and outwardly imposed form, but dynamical, a free, spontaneous spring of high purpose and feeling; not something put on, but a bent and impulse of the spirit within. Thus He gave religion an elasticity and perpetual vitality which prophesy for it permanence and power,—‘a well of water springing up unto everlasting life’ ( John 4:14). He made it (2) effectually operative ,—an energizing force, working itself out in practical life, impressing its hallowed ideas and aims on the world of affairs, and proving its reality by the heightened quality of the actions to which it leads. And He made it (3) a gracious influence ,—commending itself to the general conscience, winning reverence, inspiring self-devotion, and transmitting from heart to heart fervours of aspiration after the things of God.
Literature.—Cremer, Bib. Theol. Lex. s.v . καρδἰα; art. ‘Herz’ in PR E [Note: RE Real-Encyklopädie fur protest. Theologic und Kirche.] 3 [Note: designates the particular edition of the work referred] ; Wendt, Teaching of Jesus , i. 265 ff.; Martensen, Christian Ethics (Individual), 80 ff.; Weiss, Bib. Theol. of NT , i. 124.
G. M ‘Hardy.
Baker's Evangelical Dictionary of Biblical Theology 
"Heart" (Hebrew lebab/leb [לֵבָב], Gk. kardia [Καρδία]) occurs over one thousand times in the Bible, making it the most common anthropological term in the Scripture. It denotes a person's center for both physical and emotional-intellectual-moral activities; sometimes it is used figuratively for any inaccessible thing.
The Heart as Center of Physical Activity . "Heart" denotes to both ancient and modern peoples the beating chest organ protected by the rib cage. Ancient people, however, understood the heart's physical function differently than moderns. From their viewpoint the heart was the central organ that moved the rest of the body. Ancients ate to strengthen the heart and so revive the body. Abraham offers his weary guests food so that they might "sustain their hearts" and then go on their way ( Genesis 18:5 ). Since moderns understand the anatomy differently than the ancients, the English versions gloss the Hebrew to accommodate it to a more scientific viewpoint.
A Figure of Inaccessibility . The hiddenness and inaccessibility of the physical heart give rise to its figurative sense for anything that is remote and inaccessible. The "heart of the seas" ( Jonah 2:3 ) refers to the sea's fathomless, unapproachable depths and the "heart of the heavens" is its most unreachable height.
The Heart as Center of Hidden Emotional-Intellectual-Moral Activity . "Man looks at the outward appearance, " says Samuel, "but the lord looks at the heart" ( 1 Samuel 16:7 ). The king's heart is unsearchable to humankind ( Proverbs 25:3 ), but the Lord searches all hearts to reward all according to their conduct ( Jeremiah 17:10 ). In the time of judgment God will expose the hidden counsels of the heart ( 1 Corinthians 4:5 ).
Jesus says that the heart's secrets are betrayed by the mouth, even as a tree's fruit discloses its nature ( Matthew 12:33-34 ). "A wise man's heart guides his mouth, " says Solomon ( Proverbs 16:23 ). Most important, the mouth confesses what the heart trusts ( Romans 10:9; cf. Deuteronomy 30:14 ).
Moderns connect some of the heart's emotional-intellectual-moral functions with the brain and glands, but its functions are not precisely equivalent for three reasons.
First, moderns do not normally associate the brain/mind with both rational and nonrational activities, yet the ancients did not divorce them ( Psalm 20:4 ).
Second, the heart's reasoning, as well as its feeling, depends on its moral condition. Jesus said that "from within, out of men's hearts, come evil thoughts" ( Mark 7:21 ). Because the human heart is deceitful above all things ( Jeremiah 17:9 ) and folly is found up in the heart of a child ( Proverbs 22:15 ), the Spirit of God must give humans a new heart ( Jeremiah 31:33; Ezekiel 36:26 ) through faith that purifies it ( Acts 15:9; cf. Ephesians 3:17 ).
Third, moderns distinguish between the brain's thoughts and a person's actions, but the distinction between thought and action is inappropriate for heart. "The word is very near you, " says Moses to a regenerated Israel, "in your mouth and in your heart" ( Deuteronomy 30:14 ).
The Heart's Emotional Functions . The Lord, who knows our hearts ( Luke 16:15 ), experiences its full range of emotions: for example, its joy ( Deuteronomy 28:47; 1 Samuel 2:1; Proverbs 15:15 ) and its sorrow ( 1 Samuel 1:8 ); its raging ( 2 Kings 6:11 ) and its peace ( Colossians 3:15 ); its feeling troubled ( John 14:1 ) and its rejoicing ( 1 Samuel 2:1; Psalm 104:15 ); its love ( Romans 5:5; 1 Peter 1:22 ) and its selfish ambition ( James 3:14 ); its modes of doubts ( Mark 11:23 ) and of fear ( Genesis 42:28 ) and its mode of trusting ( Proverbs 3:5 ); when it rises up in repulsive pride ( Deuteronomy 8:14 ) or, as in the case of Jesus, is lowly and humble ( Matthew 11:29 ); and when one loses heart ( Hebrews 12:3 ) or takes heart ( John 16:33 ).
The emotional state of the heart affects the rest of a person: "A happy heart makes the face cheerful, but heartache crushes the spirit" ( Proverbs 15:13 ); "a cheerful heart is good medicine, but a crushed spirit dries up the bones" (17:22).
The heart also wishes, desires. The father warns his son against coveting the adulteress's beauty ( Proverbs 6:25 ) and against envying sinners in his heart ( Proverbs 23:17 ). Above all else the heart of a saint seeks God ( Psalm 119:2,10 ). Believers set it on things above ( Colossians 3:1 ). This is effected, says Jesus, by putting your treasures in heaven, for "where your treasure is, there your heart will be also" ( Matthew 6:21 ). If we look for God with all our heart, Moses promises we will find him ( Deuteronomy 4:28-29 ).
The Heart's Intellectual-Spiritual Functions . The heart thinks ( Matthew 9:4; Mark 2:8 ), remembers, reflects, and meditates ( Psalm 77:5-6; Luke 2:19 ). Solomon's comprehensive knowledge of flora and fauna is described as his breadth of heart ( 1 Kings 4:29 ).
More specifically, as the eyes were meant to see and the ears to hear, the heart is meant to understand, to discern, to give insight. The Alexandrian Jewish scribes translated into Greek about 200 b.c. the Hebrew text of Proverbs 2:10 , "wisdom will enter your heart" by "wisdom will come into your understanding ( dianoian [Διάνοια])" because to them it meant the same thing. When a person lacks insight the Hebrew speaks of a "lack of heart."
Understanding cannot be separated from morals. Isaiah was commissioned: "Make the heart of this people calloused; otherwise they might understand with their hearts" ( Isaiah 6:10 ). Pharaoh hardened his heart lest he hear Moses and gain insight about the Lord ( Exodus 8:15 ), and the Lord hardened it irrevocably (7:13; 9:12). Paul says of the perverse, their foolish hearts were darkened ( Romans 1:21 ); they could not see the light of moral truth. The hearts of saints, however, are enlightened (2Col 4:6; Ephesians 1:18 ).
Moderns speak of learning by heart, by which they mean rote memory. In the Bible, however, learning by heart is not like memorizing the multiplication tables; it must be mixed with spiritual affections. The Lord complains of apostate Israel that their worship "is made up only of rules taught by men" but "their hearts are far from me" ( Isaiah 29:13 ).
As the mouth reveals what is the heart, the ear determines what goes into it. The father tells his son to "store up my commands within you"; he then adds: by "turning your ear to wisdom, and you will incline your heart to understanding" ( Proverbs 2:2 ). When Moses says, "these commandments are to be upon your hearts" ( Deuteronomy 6:6 ), he commands his hearers to remain conscious of them. This idea is expressed by the metaphor of writing on the tablet of the heart ( Proverbs 3:3; Jeremiah 17:1 ). In short, the heart needs to be educated by filling it with God's word ( Proverbs 22:17-18 ). In that way a person will grow in favor and good name (3:3-4) and be safeguarded against sin ( Psalm 119:11 ).
The heart functions as the conscience. After David showed insubordination against the anointed king by cutting off the corner of his robe, his heart smote him ( 1 Samuel 24:5 ), and after Peter's sermon the audience was "cut to the heart" ( Acts 2:37 ). The heart may condemn us, but God is greater than our hearts ( 1 John 3:20 ). David prays that God would create for him a pure heart to replace his defiled conscience ( Psalm 51:10 ).
Finally, the heart plans, makes commitments, and decides. It is the inner forum where decisions are made after deliberation; here a person engages in self-talk. "In his heart a man plans his course, but the Lord determines his steps" ( Proverbs 16:9 ). Because of this critical function, the father instructs the son: "Above all else, guard your heart, for it is the wellspring of life (4:23). The Lord detests "a heart that devises wicked schemes" (6:18).
The greatest commandment according to Jesus is "Love the Lord your God with all your heart" ( Matthew 22:37 ). Love here is more than emotion; it is a conscious commitment to the Lord.
One speaks to the heart of another to move that person to a decision ( Isaiah 40:2; Hosea 2:14 ). The father asks the son for his heart ( Proverbs 23:26 ), by which he means that the son make a conscious decision to follow his instructions. The impenitent, however, have hearts that are insensitive, obstinate ( Mark 3:5; 6:52 ), and hard ( Matthew 19:8 ); they cannot be moved in a new direction.
Bruce K. Waltke
See also Hardness Of Heart Hardening
Bibliography . F. Baumgä tel et al., TDNT, 3:605-14; R. Bultnamn, Theology of the New Testament, 1:220-22; R. Jewett, Paul's Anthropological Terms ; T. Song, NIDNITT, 2:80-84; H. W. Wolff, Anthropology of the Old Testament, pp. 40-58.
Hastings' Dictionary of the Bible 
HEART. 1. Instances are not wanting in the OT of the employment of this word in a physiological sense, though they are not numerous. Jacob, for example, seems to have suffered in his old age from weakness of the heart; a sudden failure of its action occurred on receipt of the unexpected but joyful news of Joseph’s great prosperity ( Genesis 45:26 ). A similar failure proved fatal in the case of Eli, also in extreme old age ( 1 Samuel 4:13-18; cf. the case of the exhausted king, 1 Samuel 28:20 ). The effect of the rending of the pericardium is referred to by Hosea as well known ( 1 Samuel 13:8 ); and although the proverb ‘a sound (RVm [Note: Revised Version margin.] ‘tranquil’) heart is the life of the flesh’ ( Proverbs 14:30 ) is primarily intended as a psychological truth, the simile is evidently borrowed from a universally recognized physiological fact (cf. Proverbs 4:23 ). The aphorism attributed to ‘the Preacher’ ( Ecclesiastes 10:2 ) may be interpreted in the same way; the ‘right hand’ is the symbol of strength and firmness, and the left of weakness and indecision (cf. Ecclesiastes 2:14 ). Nor does it appear that OT writers were ignorant of the vital functions which the heart is called on to discharge. This will be seen by their habit of using the word metaphorically as almost a synonym for the entire life (cf. Psalms 22:26; Psalms 69:32 , Isaiah 1:5 , where ‘head’ and ‘heart’ cover man’s whole being).
2. The preponderating use of the word is, however, psychological; and it is in this way made to cover a large variety of thought. Thus it is employed to denote the centre of man’s personal activities , the source whence the principles of his action derive their origin (see Genesis 6:5; Genesis 8:21 , where men’s evil deeds are attributed to corruption of the heart). We are, therefore, able to understand the significance of the Psalmist’s penitential prayer, ‘Create in me a clean heart’ ( Psalms 51:10 ), and the meaning of the prophet’s declaration, ‘a new heart also will I give you’ ( Ezekiel 36:26; cf. Ezekiel 11:19 ). The heart, moreover, was considered to be the seat of the emotions and passions ( Deuteronomy 19:6 , 1 Kings 8:38 , Isaiah 30:29; cf. Psalms 104:15 , where the heart is said to be moved to gladness by the use of wine). It was a characteristic, too, of Hebraistic thought which made this organ the seat of the various activities of the intellect , such as understanding ( Job 34:10; Job 34:34 , 1 Kings 4:29 ), purpose or determination ( Exodus 14:5 , 1 Samuel 7:3 , 1 Kings 8:48 , Isaiah 10:7 ), consciousness ( Proverbs 14:10 , where, if EV [Note: English Version.] be an accurate tr. [Note: translate or translation.] of the original text, the heart is said to be conscious both of sorrow and of joy; cf. 1 Samuel 2:1 ), imagination (cf. Luke 1:51 , Genesis 8:21 ), memory ( Psalms 31:12 , 1 Samuel 21:12; cf. Luke 2:19; Luke 2:51; Luke 1:66 ). The monitions of the conscience are said to proceed from the heart ( Job 27:6 ), and the counterpart of the NT expression ‘branded in their own conscience as with a hot iron’ ( 1 Timothy 4:2 RV [Note: Revised Version.] ) is found in the OT words ‘I will harden his heart’ ( Exodus 4:21; cf. Deuteronomy 2:30 , Joshua 11:20 etc.). Closely connected with the idea of conscience is that of moral character, and so we find ‘a new heart’ as the great desideratum of a people needing restoration to full and intimate relationship with God ( Ezekiel 18:31; cf. Deuteronomy 9:5 , 1 Kings 11:4 ). It is, therefore, in those movements which characterize repentance, placed in antithesis to outward manifestations of sorrow for sin, ‘Rend your heart and not your garments’ ( Joel 2:13 ).
3. Moving along in the direction thus outlined, and not forgetting the influence of the Apocryphal writings on later thought (cf. e.g. Wis 8:19; Wis 17:11 , Sir 42:18 etc.), we shall be enabled to grasp the religious ideas enshrined in the teaching of the NT. In the recorded utterances of Jesus, so profoundly influenced by the ancient writings of the Jewish Church, the heart occupies a very central place. The beatific vision is reserved for those whose hearts are ‘pure’ ( Matthew 5:8; cf. 2 Timothy 2:22 , 1 Peter 1:22 RVm [Note: Revised Version margin.] ). The heart is compared to the soil on which seed is sown; it containsmoral potentialities which spring into objective existence in the outward life of the receiver ( Luke 8:15; cf., however, Mark 4:15-20 , where no mention is made of this organ; see also Matthew 13:18 , in which the heart is referred to, as in Isaiah 6:10 , as the seat of the spiritual understanding). Hidden within the remote recesses of the heart are those principles and thoughts which will inevitably spring into active life, revealing its purity or its native corruption ( Luke 6:45; cf. Matthew 12:34 f., Matthew 15:18 f.). It is thus that men’s characters reveal themselves in naked reality ( 1 Peter 3:4 ). It is the infallible index of human character, but can be read only by Him who ‘searcheth the hearts’ ( Romans 8:27; cf. 1 Samuel 16:7 , Proverbs 21:2 , Luke 16:15 ). Human judgment can proceed only according to the unerring evidence tendered by this resultant of inner forces, for ‘by their fruits ye shall know them’ ( Matthew 7:20 ). The more strictly Jewish of the NT writers show the influence of OT thought in their teaching. Where we should employ the word ‘conscience’ St. John uses ‘heart,’ whose judgments in the moral sphere are final ( 1 John 3:20 f.). Nor is St. Paul free from the influence of this nomenclature. He seems, in fact, to regard conscience as a function of the heart rather than as an independent moral and spiritual organ ( Romans 2:15 , where both words occur; cf. the quotation Hebrews 10:16 ). In spite of the fact that the last-named Apostle frequently employs the terms ‘mind,’ ‘understanding,’ ‘reason,’ ‘thinkings,’ etc., to express the elements of intellectual activity in man, we find him constantly reverting to the heart as discharging functions closely allied to these (cf. ‘the eyes of your heart,’ Ephesians 1:18; see also 2 Corinthians 4:6 ). With St. Paul, too, the heart is the seat of the determination or will (cf. 1 Corinthians 7:37 , where ‘steadfast in heart’ is equivalent to will-power). In all these and similar cases, however, it will be noticed that it is man’s moral nature that he has in view; and the moral and spiritual life, having its roots struck deep in his being, is appropriately conceived of as springing ultimately from the most essentially vital organ of his personal life.
J. R. Willis.
Holman Bible Dictionary 
First, the word heart refers to the physical organ and is considered to be the center of the physical life. Eating and drinking are spoken of as strengthening the heart ( Genesis 18:5; Judges 19:5; Acts 14:17 ). As the center of physical life, the heart came to stand for the person as a whole.
The heart became the focus for all the vital functions of the body; including both intellectual and spiritual life. The heart and the intellect are closely connected, the heart being the seat of intelligence: “For this people's heart is waxed gross lest at any time they should understand with their heart, and should be converted” ( Matthew 13:15 ). The heart is connected with thinking: As a person “thinketh in his heart, so is he” ( Proverbs 23:7 ). To ponder something in one's heart means to consider it carefully ( Luke 1:66; Luke 2:19 ). “To set one's heart on” is the literal Hebrew that means to give attention to something, to worry about it ( 1 Samuel 9:20 ). To call to heart (mind) something means to remember something ( Isaiah 46:8 ). All of these are functions of the mind, but are connected with the heart in biblical language.
Closely related to the mind are acts of the will, acts resulting from a conscious or even a deliberate decision. Thus, 2 Corinthians 9:7 : “Every man according as he purposeth in his heart, so let him give.” Ananias contrived his deed of lying to the Holy Spirit in his heart ( Acts 5:4 ). The conscious decision is made in the heart ( Romans 6:17 ). Connected to the will are human wishes and desires. Romans 1:24 describes how God gave them up “through the lusts of their own hearts, to dishonor their own bodies.” David was a man after God's “own heart” because he would “fulfill all” of God's will ( Acts 13:22 ).
Not only is the heart associated with the activities of the mind and the will, but it is also closely connected to the feelings and affections of a person. Emotions such as joy originate in the heart ( Psalm 4:7; Isaiah 65:14 ). Other emotions are ascribed to the heart, especially in the Old Testament. Nabal's fear is described by the phrase: “his heart died within him” ( 1 Samuel 25:37; compare Psalm 143:4 ). Discouragement or despair is described by the phrase “heaviness in the heart” which makes it stoop ( Proverbs 12:25 ). Again, Ecclesiastes 2:20 says, “Therefore I went about to cause my heart to despair of all the labor which I took under the sun.” Another emotion connected with the heart is sorrow. John 16:6 says, “because I have said these things unto you, sorrow hath filled your heart.” Proverbs 25:20 , describes sorrow as having “an heavy heart.” The heart is also the seat of the affection of love and its opposite, hate. In the Old Testament, for example, Israel is commanded: “You shall not hate your brother in your heart, but you shall reason with your neighbor, lest you bear sin because of him” ( Leviticus 19:17 Rsv). A similar attitude, bitter jealousy, is described in James 3:14 as coming from the heart. On the other hand, love is based in the heart. The believer is commanded to love God “with all your heart” ( Mark 12:30; compare Deuteronomy 6:5 ). Paul taught that the purpose of God's command is love which comes from a “pure heart” ( 1 Timothy 1:5 ).
Finally, the heart is spoken of in Scripture as the center of the moral and spiritual life. The conscience, for instance, is associated with the heart. In fact, the Hebrew language had no word for conscience, so the word heart was often used to express this concept: “my heart shall not reproach me so long as I live” ( Job 27:6 ). The Revised Standard Version translates the word for “heart” as “conscience” in 1 Samuel 25:31 (RSV). In the New Testament the heart is spoken of also as that which condemns us ( 1 John 3:19-21 ). All moral conditions from the highest to the lowest are said to center in the heart. Sometimes the heart is used to represent a person's true nature or character. Samson told Delilah “all his heart” ( Judges 16:17 ). This true nature is contrasted with the outward appearance: “man looks on the outward appearance, but the Lord looks on the heart” ( 1 Samuel 16:7 RSV).
On the negative side, depravity is said to issue from the heart: “The heart is deceitful above all things, and desperately wicked: who can know it?” ( Jeremiah 17:9 ). Jesus said that out of the heart comes evil thoughts, murder, adultery, fornication, theft, false witness, slander ( Matthew 15:19 ). In other words, defilement comes from within rather than from without.
Because the heart is at the root of the problem, this is the place where God does His work in the individual. For instance, the work of the law is “written in their hearts,” and conscience is the proof of this ( Romans 2:15 ). The heart is the field where seed (the Word of God) is sown ( Matthew 13:19; Luke 8:15 ). In addition to being the place where the natural laws of God are written, the heart is the place of renewal. Before Saul became king, God gave him a new heart ( 1 Samuel 10:9 ). God promised Israel that He would give them a new spirit within, take away their “stony heart” and give them a “heart of flesh” ( Ezekiel 11:19 ). Paul said that a person must believe in the heart to be saved, “for with the heart man believeth unto righteousness” ( Romans 10:10 ). (See also Mark 11:23; Hebrews 3:12 .)
Finally, the heart is the dwelling place of God. Two persons of the Trinity are said to reside in the heart of the believer. God has given us the “earnest of the Spirit in our hearts” ( 2 Corinthians 1:22 ). Ephesians 3:17 expresses the desire that “Christ may dwell in your hearts by faith.” The love of God “is shed abroad in our hearts by the Holy Ghost which is given unto us” ( Romans 5:5 ).
Vine's Expository Dictionary of OT Words 
Lêb ( לֵב , Strong'S #3820), “heart; mind; midst.” Lêb and its synonym lêbab —appear 860 times in the Old Testament. The law, prophets, and Psalms often speak of the “heart.” The root occurs also in Akkadian, Assyrian, Egyptian, Ugaritic, Aramaic, Arabic, and post-biblical Hebrew. The corresponding Aramaic nouns occur seven times in the Book of Daniel.
“Heart” is used first of man in Gen. 6:5: “And God saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually.” In Gen. 6:6 lêb is used of God: “And it repented the Lord that he had made man on the earth, and it grieved him at his heart.”
“Heart” may refer to the organ of the body: “And Aaron shall bear the names of the children of Israel in the breastplate of judgment upon his heart, when he goeth in unto the holy place …” (Exod. 28:29); “… [Joab] took three darts in his hand, and thrust them through the heart of Absalom …” (2 Sam. 18:14); “My heart panteth …” (Ps. 38:10). Lêb may also refer to the inner part or middle of a thing: “… and the depths were congealed in the heart of the sea” (Exod. 15:8); “… and the mountain burned with fire in the midst [RSV, “to the heart”] of heaven …” (Deut. 4:11, KJV)“Yea, thou shalt be as he that lieth down in the midst of the sea …” (Prov. 23:34).
Lêbab can be used of the inner man, contrasted to the outer man, as in Deut. 30:14: “But the word is very nigh unto thee, in thy mouth, and in thy heart, that thou mayest do it” (cf. Joel 2:13); “… man looketh on the outward appearance, but the Lord looketh on the heart” (1 Sam. 16:7). Lêbab —is often compounded with “soul” for emphasis, as in 2 Chron. 15:12; “And they entered into a covenant to seek the Lord God of their fathers with all their heart and with all their soul” (cf. 2 Chron. 15:15). Nepesh (“soul; life; self”) is translated “heart” fifteen times in the KJV. Each time, it connotes the “inner man”: “For as he thinketh in his heart [ nepesh ], so is he” (Prov. 23:7).
Lêb can be used of the man himself or his personality: “Then Abraham fell upon his face and laughed, and said in his heart, …” (Gen. 17:17); “… my heart had great experience …” (Eccl. 1:16). Lêb is also used of God in this sense: “And I will give you pastors according to mine heart” (Jer. 3:15).
The seat of desire, inclination, or will can be indicated by “heart”: “Pharaoh’s heart is hardened …” (Exod. 7:14); “… whosoever is of a willing heart, let him bring it …” (Exod. 35:5; cf. vv. 21, 29); “I will praise thee, O Lord my God, with all my heart …” (Ps. 86:12). Lêb is also used of God in this sense: “… and I will plant them in this land assuredly with my whole heart and with my whole soul” (Jer. 32:41). Two people are said to be in agreement when their “hearts” are right with each other: “Is thine heart right, as my heart is with thy heart?” (2 Kings 10:15). In 2 Chron. 24:4, “… Joash was minded to repair the house of the Lord” (Heb. “had in his heart”). The “heart” is regarded as the seat of emotions: “And thou shalt love the Lord thy God with all thine heart, …” (Deut. 6:5); “… and when he [Aaron] seeth thee, he will be glad in his heart” (Exod. 4:14; cf. 1 Sam. 2:1). So there are “merry” hearts (Judg. 16:25), “fearful” hearts (Isa. 35:4), and hearts that “trembled” (1 Sam. 4:13).
The “heart” could be regarded as the seat of knowledge and wisdom and as a synonym of “mind.” This meaning often occurs when “heart” appears with the verb “to know”: “Thus you are to know in your heart …” (Deut. 8:5, NASB); and “Yet the Lord hath not given you a heart to perceive [know] …” (Deut. 29:4, Kjv; Rsv “mind”). Solomon prayed, “Give therefore thy servant an understanding heart to judge thy people, that I may discern between good and bad …” (1 Kings 3:9; cf. 4:29). Memory is the activity of the “heart,” as in Job 22:22: “… lay up his [God’s] words in thine heart.”
The “heart” may be the seat of conscience and moral character. How does one respond to the revelation of God and of the world around him? Job answers: “… my heart shall not reproach me as long as I live” (27:6). On the contrary, “David’s heart smote him …” (2 Sam. 24:10). The “heart” is the fountain of man’s deeds: “… in the integrity of my heart and innocency of my hands I have done this” (Gen. 20:5; cf. v. 6). David walked “in uprightness of heart” (1 Kings 3:6) and Hezekiah “with a perfect heart” (Isa. 38:3) before God. Only the man with “clean hands, and a pure heart” (Ps. 24:4) can stand in God’s presence.
Lêb may refer to the seat of rebellion and pride. God said: “… for the imagination of man’s heart is evil from his youth” (Gen. 8:21). Tyre is like all men: “Because thine heart is lifted up, and thou hast said, I am a God” (Ezek. 28:2). They all become like Judah, whose “sin … is graven upon the table of their heart” (Jer. 17:1).
God controls the “heart.” Because of his natural “heart,” man’s only hope is in the promise of God: “A new heart also will I give you, … and I will take away the stony heart out of your flesh, and I will give you a heart of flesh” (Ezek. 36:26). So the sinner prays: “Create in me a clean heart, O God” (Ps. 51:10); and “… unite my heart [give me an undivided heart] to fear thy name” (Ps. 86:11). Also, as David says, “I know also, my God, that thou triest the heart, and hast pleasure in uprightness” (1 Chron. 29:17). Hence God’s people seek His approval: “… try my reins and my heart” (Ps. 26:2).
The “heart” stands for the inner being of man, the man himself. As such, it is the fountain of all he does (Prov. 4:4). All his thoughts, desires, words, and actions flow from deep within him. Yet a man cannot understand his own “heart” (Jer. 17:9). As a man goes on in his own way, his “heart” becomes harder and harder. But God will circumcise (cut away the uncleanness of) the “heart” of His people, so that they will love and obey Him with their whole being (Deut. 30:6).
Lêb ( לֵב , Strong'S #3820), “tenderly; friendly; comfortably.” Lêb is used as an adverb in Gen. 34:3: “And his soul clave unto Dinah … and he loved the damsel, and spake kindly unto the damsel.” In Ruth 4:13, the word means “friendly”: “… thou hast spoken friendly unto thine handmaid.…” The word means “comfortably” in 2 Chron. 30:22 and in Isa. 40:2.
Charles Buck Theological Dictionary 
Is used for the soul, and all the powers thereof; as the understanding , conscience, will, affections, and memory. The heart of man is naturally, constantly, universally, inexpressibly, openly, and evidently depraved, and inclined to evil, Jeremiah 17:9 . It requires a divine power to renovate it, and render it susceptible of right impressions, Jeremiah 24:7 . When thus renovated, the effects will be seen in the temper, conversation, and conduct at large.
See Faith, Hope &c. Hardness of heart is that state in which a sinner is inclined to, and actually goes on in rebellion against God. This state evidences itself by light views of the evil of sin; partial acknowledgment and confession of it; frequent commission of it; pride and conceit: ingratitude; unconcern about the word and ordinances of God; inattention to divine providences; stifling convictions of conscience; shunning reproof; presumption, and general ignorance of divine things. We must distinguish, however, between that hardness of heart which even a good man complains of, and that of a judicial nature.
1. Judicial hardness is very seldom perceived, and never lamented; a broken and contrite heart is the least thing such desire; but it is otherwise with believers, for the hardness they feel is always a matter of grief to them, Romans 7:24 .
2. Judicial hardness is perpetual; or, if ever there be any remorse or relenting, it is only at such times when the sinner is under some outward afflictions, or filled with the dread of the wrath of God; but as this wears off or abates, his stupidity returns as much or more than ever, Exodus 9:27; but true believers, when no adverse dispensations trouble them, are often distressed because their hearts are no more affected in holy duties, or inflamed with love to God, Romans 7:15 .
3. Judicial hardness is attended with a total neglect of duties, especially those that are secret; but that hardness of heart which a believer complains of, though it occasions his going uncomfortably in duty, yet does not keep him from it, Job 23:2; Job 3:1-26 :
4. when a person is judicially hardened, he makes use of indirect and unwarrantable methods to maintain that false peace which he thinks himself happy in the enjoyment of; but a believer, when complaining of the hardness of his heart, cannot be satisfied with any thing short of Christ, Psalms 101:2 .
5. Judicial hardness generally opposes the interest of truth and godliness; but a good man considers this as a cause nearest his heart; and although he have to lament his lukewarmness, yet he constantly desires to promote it, Psalms 72:19 . Keeping the heart, is a duty enjoined in the sacred Scriptures. It consists, says Mr. Flavel, in the diligent and constant use and improvement of all holy means and duties to preserve the soul from sin, and maintain communion with God; and this, he properly observes, supposed a previous work of sanctification, which hath set the heart right by giving it a new bent and inclination.
1. It includes frequent observation of the frame of the heart, Psalms 77:6 .
2. Deep humiliation for heart evils and disorders, 2 Chronicles 32:26 .
3. Earnest supplication for heart purifying and rectifying grace, Psalms 19:1-14
4. A constant holy jealousy over our hearts, Proverbs 27:14 .
5. It includes the realizing of God's presence with us, and setting him before us, Psalms 16:8 . Genesis 17:1 . This is,
1. The hardest work; heart work is hard work, indeed.
2. Constant work, Exodus 17:12 .
3. The most important work, Proverbs 23:1-35 This is a duty which should be attended to, if we consider it in connection with,
1. The honour of God, Is. 66: 3.
2. The sincerity of our profession, 2 Kings 10:31 . Ezekiel 33:31; Ezekiel 32:1-32 :
3. The beauty of our conversation, Proverbs 12:26 . Psalms 45:1 .
4. The comfort of our souls, 2 Corinthians 13:5 .
5. The improvement of our graces, Psalms 63:5; Psalms 6:1-10 :
6. The stability of our souls in the hour of temptation, 1 Corinthians 16:13 .
The seasons in which we should more particularly keep our hearts are,
1. The time of prosperity, Deuteronomy 6:10; Deuteronomy 12:1-32 :
2. Under afflictions, Hebrews 7:5; Hebrews 6:1-20 :
3. The time of Sion's troubles, Psalms 46:1-11
4. In the time of great and threatened dangers, Is. 26: 20, 21.
5. Under great wants, Philippians 4:6-7 .
6. In the time of duty, Leviticus 10:3 .
7. Under injuries received, Romans 12:17 , &c.
8. In the critical hour of temptation. Matthew 26:41 .
9. Under dark and doubting seasons, Hebrews 12:8 . Is. 50: 10.
10. In time of opposition and suffering, 1 Peter 4:12-13 .
11. The time of sickness and death, Jeremiah 49:11 . The means to be made use of to keep our hearts, are,
1. Watchfulness, Mark 13:37 .
2. Examination, Proverbs 4:26 .
3. Prayer, Luke 18:1 .
4. Reading God's word, John 5:39 .
5. Dependence on divine grace, Psalms 86:1-17 .
See Flavel on Keeping the Heart; Jameison's Sermons on the Heart; Wright on self-possession; Ridgley's Div. qu. 20.
Wilson's Dictionary of Bible Types 
The word "heart" is used in the Scriptures to indicate many attitudes of the mind and many various kinds of affections and reactions. It is described as being deceitful in Jeremiah 17:9. This evidently means that it will lead us astray by its feelings and its attitudes so that we must not trust in our own desires, but rather be led by the Word of GOD.
We read that the Lord searches the heart, Jeremiah 17:10. By this is indicated that the Lord examines our motives, desires and feelings to see if they agree with His will.
In Joshua 24:23 we read about the heart that is inclined to the Lord.
Our Lord spoke of being "in the heart of the earth." Matthew 12:40. This does not refer to the grave which is on the surface of the earth. It refers to hell, which is actually in the center of this earth. The Lord Jesus did go down to that part of hell where the Old Testament saints were kept in conscious comfort until the Lord JESUS would shed His Blood for them. After Calvary, He went down into this place and "led captivity captive." They were now ready to go into GOD's presence because His Blood had blotted out their sins. The blood of the sacrifices which they had brought only covered their sins.
There is an honest and good heart described in Luke 8:15. This refers to that sweet attitude of confidence and trust in GOD wherein the person listens with a hunger and a thirst for the revelation of GOD's will through His Word. It indicates that this person loves to receive GOD's instructions, and to accept GOD's provisions.
A broken heart is described in Psalm 34:18, and Psalm 51:17. By this expression is meant that deep grief has fallen upon that friend, tears have flowed, the shadows have fallen, and grief has stricken the spirit.
In Hebrews 3:12 we read of an "evil heart of unbelief in departing from the living God." Those who are afflicted in this way are those who doubt GOD, refuse to believe His promise, and seek relief from some other source. They do not believe that GOD is a living Person who will actually work on their behalf.
At the end of the Old Testament in Malachi 4:6, we read of a heart that is turned unto the Lord. This is a work of the Spirit of GOD in causing the mind and the desire of the person to come back to GOD from paths of disobedience and sin.
The stony heart is described in Ezekiel 11:19, and chapter 36:26. This describes the person who steadfastly and stubbornly refuses to believe GOD's Word, and will not have the authority of GOD in his life. He is not moved by any preaching, nor stirred by any invitation. The Word of GOD makes no impression on his soul.
The heart that fails describes that one who is overcome with fear, horror and despair. He has no strength left for the conflict. He is made weak. He seems to be helpless and hopeless. This heart is described in1Sa17:32, and in Luke 21:26.
We read in2Co3:3 of the fleshy heart. This passage really refers to the physical heart which is made of flesh. Somehow and in some mysterious way the Spirit of GOD works in our souls to bring about deep feelings of worship, love and devotion. One really does feel it in the bosom when those emotions arise.
The understanding heart is mentioned in1Ki3:9,12. The thought is that there is a deep and confiding trustful interest in GOD and in His Word. The figure is in contrast with a simple, mental knowledge which does not affect the life nor the actions.
The expression found in Luke 24:25 "slow of heart" refers to, that attitude of the heart wherein the person questions the truth of GOD's statements, and hesitates about believing in the Word and work of Christ Jesus
One miracle of GOD's grace is found in the expression "the multitude was of one heart."
Acts 4:32. By this we understand that all this great crowd thought alike, felt alike, acted alike, and planned alike. What a wonderful church this would make. The expression "lay it to heart" describes that attitude in which one will accept the Word that he hears, and will apply it to his own soul. He will make the message a personal message to his own self, and will seek to act upon it. This is true in Ecclesiastes 7:2; Isaiah 47:7; Malachi 2:2.
Genesis 6:6 (a) This represents GOD's innermost feelings in regard to His dealings and relationships with men.
Job 23:16 (a) The troubles and sorrows that had come upon Job caused him to be very tender and soft in his spirit so that there was no pride, hardness, nor self-sufficiency in his heart.
Proverbs 16:1 (a) By this figure is represented the feelings and the desires of men.
Jeremiah 17:9-10 (a) This type represents the purposes and the desires which actuate the thoughts and actions of men.
Mark 7:21 (a) This figure represents the soul and mind of a human being, his innermost self, his real self.
Bridgeway Bible Dictionary 
Both Old and New Testaments speak repeatedly of the heart as the centre of a person’s inner life. An examination of the hundreds of references to the heart in the Bible will show that the word is not limited in its meaning to one particular part of a person.
‘Heart’ may refer to a person’s whole inner life – what the person really is ( 1 Samuel 16:7; Psalms 22:26; Proverbs 4:23; Matthew 22:37; 1 Thessalonians 2:4); or it may refer to attributes of human personality such as a person’s understanding ( 1 Kings 3:9; Proverbs 2:10; 1 Corinthians 2:9; Ephesians 1:18), desires ( Deuteronomy 24:15; Proverbs 6:25; Matthew 6:21; Romans 1:24), feelings ( Judges 19:6; Proverbs 14:10; Proverbs 15:30; John 14:27; James 3:14), determination ( Exodus 8:15; 1 Kings 8:58; Romans 6:17; Colossians 3:22), or character ( 1 Samuel 13:14; Jeremiah 5:23; Romans 2:29; 2 Thessalonians 3:5; 1 Peter 3:4).
Sometimes ‘heart’ is used as another word for a person’s spirit ( Psalms 51:10; Psalms 51:17; Ezekiel 36:26), soul ( Deuteronomy 4:29; Proverbs 2:10; Acts 4:32) or mind ( 1 Samuel 2:35; Ephesians 1:18; Hebrews 8:10; cf. Matthew 22:37). (See also Humanity, Humankind; Mind; Soul; Spirit )
The heart is what is sometimes referred to as ‘the inner being’, and is the source of all the wrong that a person does ( Proverbs 6:14; Proverbs 6:18; Jeremiah 17:9; Mark 7:21-23; Romans 1:24-25; Ephesians 4:18; see Sin ). Therefore, the heart must be cleansed to bring forgiveness; or, to use another picture, it must be re-created to bring new spiritual life. Only God can bring about this cleansing or re-creation ( Psalms 51:10; Ezekiel 36:26; Acts 8:21-22; Ephesians 3:16; Hebrews 10:22).
Since the heart determines actions, a person must be careful to have right attitudes of heart at all times ( Leviticus 19:17; Psalms 4:4; 1 Timothy 1:5; James 3:14). God sees the inner condition and judges the person accordingly ( 1 Samuel 16:7; Psalms 44:21; Matthew 5:8; Revelation 2:23; see also Conscience ).
King James Dictionary 
HEART, n. L. cor, cordis, and allied to Eng.core, or named from motion, pulsation.
1. A muscular viscus, which is the primary organ of the blood's motion in an animal body, situated in the thorax. From this organ all the arteries arise, and in it all the veins terminate. By its alternate dilatation and contraction, the blood is received from the veins, and returned through the arteries, by which means the circulation is carried on and life preserved. 2. The inner part of any thing the middle part or interior as the heart of a country, kingdom or empire the heart of a town the heart of a tree. 3. The chief part the vital part the vigorous or efficacious part. 4. The seat of the affections and passions, as of love, joy, grief, enmity, courage, pleasure &c.
The heart is deceitful above all things. Every imagination of the thoughts of the heart is evil continually. We read of an honest and good heart, and an evil heart of unbelief, a willing heart, a heavy heart, sorrow of heart, a hard heart, a proud heart, a pure heart. The heart faints in adversity, or under discouragement, that is, courage fails the heart is deceived, enlarged, reproved, lifted up, fixed, established, moved, &c.
5. By a metonymy, heart is used for an affection or passion, and particularly for love.
The king's heart was towards Absalom. 2 Samuel 14 .
6. The seat of the understanding as an understanding heart. We read of men wise in heart, and slow of heart. 7. The seat of the will hence, secret purposes, intentions or designs. There are many devices in a man's heart. The heart of kings is unsearchable. The Lord tries and searches the heart. David had it in his heart to build a house of rest for the ark.
Sometimes heart is used for the will, or determined purpose.
The heart of the sons of men is fully set in them to do evil. Ecclesiastes 8
8. Person character used with respect to courage or kindess.
Cheerly, my hearts.
Michal saw king David leaping and dancing before the Lord, and she despised him in her heart. 2 Samuel 6
11. Disposition of mind.
He had a heart to do well.
12. Secret meaning real intention.
And then show you the heart of my message.
13. Conscience, or sense of good or
Every man's heart and conscience--doth either like or disallow it.
14. Strength power of producing vigor fertility. Keep the land in heart.
That the spent earth may gather heart again.
15. The utmost degree.
This gay charm--hath beguiled me
To the very heart of loss.
To get or learn by heart, to commit to memory to learn so perfectly as to be able to repeat without a copy.
To take to heart, to be much affected also, to be zealous, ardent or solicitous about a thing to have concern.
To lay to heart, is used nearly in the sense of the foregoing.
To set the heart on, to fix the desires on to be very desirous of obtaining or keeping to be very fond of.
To set the heart at rest, to make one's self quiet to be tranquil or easy in mind.
To find in the heart, to be willing or disposed.
I find it in my heart to ask your pardon.
For my heart, for tenderness or affection.
I could not for my heart refuse his request.
Or, this phrase may signify, for my life if my life was at stake.
I could not get him for my heart to do it.
To speak to one's heart,in Scripture, to speak kindly to to comfort to encourage.
To have in the heart, to purpose to have design or intention.
A hard heart, cruelty want of sensibility.
Watson's Biblical & Theological Dictionary 
The Hebrews regarded the heart as the source of wit, understanding, love, courage, grief, and pleasure. Hence are derived many modes of expression. "An honest and good heart," Luke 8:15 , is a heart studious of holiness, being prepared by the Spirit of God to receive the word with due affections, dispositions, and resolutions. We read of a broken heart, a clean heart, an evil heart, a liberal heart. To "turn the heart of the fathers to the children, and the heart of the children to their fathers,"
Malachi 4:6 , signifies to cause them to be perfectly reconciled, and that they should be of the same mind. To want heart, sometimes denotes to want understanding and prudence: "Ephraim is like a silly dove, without heart," Hosea 7:11 . "O fools, and slow of heart," Luke 24:25; that is, ignorant, and without understanding. "This people's heart is waxed gross, lest they should understand with their heart," Matthew 13:15; their heart is become incapable of understanding spiritual things; they resist the light, and are proof against all impressions of truth. "The prophets prophesy out of their own heart," Ezekiel 13:2; that is, according to their own imagination, without any warrant from God.
The heart is said to be dilated by joy, contracted by sadness, broken by sorrow, to grow fat, and be hardened by prosperity. The heart melts under discouragement, forsakes one under terror, is desolate in affliction, and fluctuating in doubt. To speak to any one's heart is to comfort him, to say pleasing and affecting things to him. The heart expresses also the middle part of any thing: "Tyre is in the heart of the seas," Ezekiel 27:4; in the midst of the seas. "We will not fear though the mountains be carried into the heart (middle) of the sea," Psalms 46:2 .
The heart of man is naturally depraved and inclined to evil, Jeremiah 17:9 . A divine power is requisite for its renovation, John 3:1-11 . When thus renewed, the effects will be seen in the temper, conversation, and conduct at large. Hardness of heart is that state in which a sinner is inclined to, and actually goes on in, rebellion against God.
Webster's Dictionary 
(1): ( n.) A hollow, muscular organ, which, by contracting rhythmically, keeps up the circulation of the blood.
(2): ( v. t.) To give heart to; to hearten; to encourage; to inspirit.
(3): ( v. i.) To form a compact center or heart; as, a hearting cabbage.
(4): ( n.) One of a series of playing cards, distinguished by the figure or figures of a heart; as, hearts are trumps.
(5): ( n.) That which resembles a heart in shape; especially, a roundish or oval figure or object having an obtuse point at one end, and at the other a corresponding indentation, - used as a symbol or representative of the heart.
(6): ( n.) Courage; courageous purpose; spirit.
(7): ( n.) A term of affectionate or kindly and familiar address.
(8): ( n.) The nearest the middle or center; the part most hidden and within; the inmost or most essential part of any body or system; the source of life and motion in any organization; the chief or vital portion; the center of activity, or of energetic or efficient action; as, the heart of a country, of a tree, etc.
(9): ( n.) The seat of the affections or sensibilities, collectively or separately, as love, hate, joy, grief, courage, and the like; rarely, the seat of the understanding or will; - usually in a good sense, when no epithet is expressed; the better or lovelier part of our nature; the spring of all our actions and purposes; the seat of moral life and character; the moral affections and character itself; the individual disposition and character; as, a good, tender, loving, bad, hard, or selfish heart.
(10): ( n.) Vigorous and efficient activity; power of fertile production; condition of the soil, whether good or bad.
(11): ( n.) Vital part; secret meaning; real intention.
Easton's Bible Dictionary 
Deuteronomy 6:5 26:16 Matthew 22:37 Mark 12:30,33
The heart is the "home of the personal life," and hence a man is designated, according to his heart, wise ( 1 Kings 3:12 , etc.), pure ( Psalm 24:4; Matthew 5:8 , etc.), upright and righteous ( Genesis 20:5,6; Psalm 11:2; 78:72 ), pious and good ( Luke 8:15 ), etc. In these and such passages the word "soul" could not be substituted for "heart."
The heart is also the seat of the conscience ( Romans 2:15 ). It is naturally wicked ( Genesis 8:21 ), and hence it contaminates the whole life and character ( Matthew 12:34; 15:18; Compare Ecclesiastes 8:11; Psalm 73:7 ). Hence the heart must be changed, regenerated ( Ezekiel 36:26; 11:19; Psalm 51:10-14 ), before a man can willingly obey God.
The process of salvation begins in the heart by the believing reception of the testimony of God, while the rejection of that testimony hardens the heart ( Psalm 95:8; Proverbs 28:14; 2 Chronicles 36:13 ). "Hardness of heart evidences itself by light views of sin; partial acknowledgment and confession of it; pride and conceit; ingratitude; unconcern about the word and ordinances of God; inattention to divine providences; stifling convictions of conscience; shunning reproof; presumption, and general ignorance of divine things."
People's Dictionary of the Bible 
Heart. Acts 16:14 The seat of the affections, desires, hopes, and motives. John 14:1; Esther 1:10. The term is also used by the Bible writers to designate the understanding, 1 Corinthians 2:9, and intellectual perceptions. It is further a general term for the spiritual nature of man. Isaiah 1:5; 2 Corinthians 4:6. In the latter passage the apostle speaks of the light shining in our hearts, teaching us of Christ as the one who reveals God. The heart is declared to be corrupt and full of evil, Ecclesiastes 9:3, and deceit, Jeremiah 17:9, the seat of sin and crime, Matthew 15:19, as also of faith. Romans 10:10. The Lord "looketh on the heart," 1 Samuel 16:7, in contrast to the outward appearance, and we are commanded to cultivate it, as the most important part of our nature, rather than external appearances. Proverbs 4:4; Joel 2:13. The expression, "to speak in the heart," 1 Samuel 1:13, is synonymous with "to think."
Morrish Bible Dictionary 
The heart is often referred to in scripture as the seat of the affections and of the passions, also of wisdom and understanding hence we read of 'the wise in heart,' also the Lord gave to Solomon 'a wise and understanding heart.' It is the centre of a man's being. But before the deluge God's verdict of man was that every imagination of the thoughts of his heart was only evil continually. Genesis 6:5 . A similar verdict is found in Genesis 8:21 , after Noah came out of the ark. And the Lord said, Out of the heart of man proceed evil thoughts and every form of wickedness. Mark 7:21 . The law required man to love God with all his heart. The reception of the gospel must be in the heart, Romans 10:9; and God enables a hearer to receive the good news in 'an honest and good heart,' upon which there is fruit. Luke 8:15 . In new creation there is a 'pure heart,' the Christian being led by the Holy Spirit. 1 Timothy 1:5; 2 Timothy 2:22; 1 Peter 1:22 .
Vine's Expository Dictionary of NT Words 
"hardness of heart" (skleros, "hard," and kardia), is used in Matthew 19:8; Mark 10:5; 16:14 . In the Sept., Deuteronomy 10:16; Jeremiah 4:4 .
Fausset's Bible Dictionary 
Often including the intellect as well as the affections and will; as conversely the "mind" often includes the feeling and will as well as the intellect. Romans 1:21, "their foolish heart was darkened." Ephesians 1:18, "the eyes of your understanding (the Vaticanus manuscript; but the Sinaiticus and Alexandrinus manuscripts 'heart') being enlightened." Thus, the Scripture implies that the heart and the head act and react on one another; and in men's unbelief it is the will that perverts the intellectual perceptions. John 7:17, "if any man be willing to (Greek) do, he shall know." "Willingness to obey" is the key to spiritual knowledge. See Jeremiah 17:9; Hosea 7:11, "Ephraim is like a silly dove without heart," i.e. "moral understanding".
Hawker's Poor Man's Concordance And Dictionary 
The heart in all languages is considered as the leading principle of action and of character.
"A good man, (saith the Lord Jesus) out of the good treasure of his heart, bringeth forth that which is good; and an evil man, out of the evil treasure of his heart, bringeth forth that which is evil; for out of the abundance of the heart the mouth speaketh." ( Luke 6:45) Hence a change of circumstances in spiritual concerns, from darkness to light, is called"the taking away the heart of stone, and giving an heart of flesh, turning the heart of the fathers to the children, and the children to the fathers."Hence the Lord saith, in reference to his whole church, "I will give them one heart, and one way, that they may fear me for ever." ( Jeremiah 32:39)
Cyclopedia of Biblical, Theological and Ecclesiastical Literature 
in the Biblical sense ( Καρδία ; לֵב or לֵבָב , often exchanged for קֶרֶב , in a more extended sense, as in Psalms 39:3-4; Psalms 109:22; 1 Samuel 25:37, the whole region of the chest, with its contents; see Delitzsch, System Of Biblical Psychology, § 12, 13. According to Hupfeld, חֵלֶב , in Psalms 17:10, and Psalms 73:7, means simply The Heart, which is not very likely).
1. In the Biblical point of view, human life, in all its operations, is centered in the heart. The heart is the central organ of the physical circulation; hence the necessity for strengthening the body as a support for the heart ( סָעִד לֵב , Genesis 18:5; Judges 19:5; Psalms 104:15); and the exhaustion of physical power is called a drying up of the heart ( Psalms 102:5; Psalms 22:15, etc.). So, also, is the heart the center of spiritual activity; for all spiritual aims, whether belonging to the intellectual, moral, or pathological spheres, are elaborated in the heart, and again carried out by the heart. In fact, the whole life of the soul, in the lower and sensual, as well as in the higher spheres, has its origin in the heart ( Proverbs 4:23, For out of it are the issues of life"). In order to follow this train of thought, and to establish in a clearer light the Biblical view of the heart, it will be best to consider the relation the heart bears to the soul ( Ψυχή , נֶפֶשׁ ). This is one of the difficult questions in Biblical psychology; Olshausen (in the Abh. de naturae humanae trichotomia, opusc. theol. p. 159) says, "Omnium longe difficillimum est accurate definire quidnam discrimen in N.T. inter Ψυχήν et Καρδίαν , intercedat." Nevertheless, the task is facilitated by the fact that there is essential agreement on this point in the anthropologies of the Old and New Testament.
(1) We first note that, while, as before said, the heart is the center of all the functions of the soul's life, the terms "heart" and "soul" are often used interchangeably in Scripture. Thus, in Deuteronomy 6:5 (compare Matthew 22:37; Mark 12:30; Mark 12:33; Luke 10:27), and Deuteronomy 26:16, we are commanded to love God and obey his commandments with all our heart and all our soul (compare 1 Chronicles 28:9); the union of the faithful, in Acts 4:12, is designated as Ην Ἡ Καρδία Καἱ Ἡ Ψυχὴ Μία . (In these passages, as in others, for instance, Deuteronomy 11:18; Deuteronomy 30:2; Jeremiah 32:41, there is, moreover, to be noticed that the heart is always named first.) Thus the indecision and division of the inner life can be designated either by Δίψυχος ( James 1:8) or by Καρδία Δισσή . It is said of both Ἁγνιζειν Καρδίας ( James 4:8) and Ἁγνίζειν Ψυχάς ( 1 Peter 1:22); also שָׁפִךְ נָפְשׁוֹ ( Psalms 42:5; comp. Job 30:16) and שָׁפִךְ לַבּוֹ ( Lamentations 2:10; Psalms 62:9), the self-impelling to the love of God applies as well to the soul (Psalms 103) as to the קְכַבַים , of which the heart is the center, etc. But in the majority of passages, where either the heart or the soul are separately spoken of, the term "heart" can either not be exchanged at. all for the term "soul," or else only with some modification in the meaning.
(2) Note also the following fundamental distinction: The Soul is the bearer of the personality (i.e. of the Ego, the proper self) of man, in virtue of the indwelling Spirit ( Proverbs 20:27; 1 Corinthians 2:11), but yet is not itself The Person of man; the heart, on the contrary (the חִדנְרֵי בֶטֶן , Proverbs 20:27), is the place where the process of self-consciousness is developed, in which the soul finds itself, and thus becomes conscious of its actions and impressions as its own ("in corde actiones animae humanae ad ipsam redeunt," as is concisely and correctly said by Roos in his Fundam. psychol. ex s. scr., 1769, p. 99). Accordingly the soul, not the heart, is spoken of when the 8:39; Luke 16:15; Proverbs 17:3; Psalms 7:10; Psalms 17:3; Jeremiah 11:20). Therefore also man is designated according to his heart in all that relates to habitual moral qualities; thus we read of a wise heart ( 1 Kings 5:12; Proverbs 10:8, etc.), a pure heart ( Psalms 41:12; Matthew 5:8; 1 Timothy 1:5; 2 Timothy 2:22), an upright and righteous heart ( Genesis 20:5-6; Psalms 11:2; Psalms 78:72; Psalms 101:2), a single heart ( Ephesians 5:5; Colossians 3:22), a pious and good heart ( Luke 8:15), a lowly heart ( Matthew 11:29), etc. In all these places it would be difficult to introduce נֶפֶשׁ or Ψυχή :
(2) We must also observe that the original divine rule of conduct for man was implanted in his heart, and therefore the heart is the seat of the Συνείδησις , or Conscience, which has a mission to proclaim that rule ( Romans 2:15). All subsequent divine revelations were also directed to the heart ( Deuteronomy 6:6); so the law demands that God should be loved with the whole heart, and then, as though by radiation from this center, with the whole soul (comp. Deuteronomy 11:18; Psalms 119:11, etc.). The teaching of wisdom also enters the heart, and from thence spreads its healing and vivifying influence through the whole organism ( Proverbs 4:21-23). The prophetic consolations must speak to the heart ( Isaiah 40:2), in contradistinction from such consolations as do not reach the bottom of human nature; thus also in Matthew 13:9; Luke 8:15, we find the heart described as the ground on which the seed of the divine Word is to be — sowed. That which becomes assimilated to the heart constitutes The Θησαυρὸς Τῆς Καρδίας ( Matthew 12:35). This, however, may not only be Ἀγαθός , but also Πονηρὀς ; for the human heart is not only a recipient of divine principles of life, but also of evil.
(3) In opposition to the superficial doctrine which makes man in regard to morals an indifferent being, Scripture presents to us the doctrine of the natural wickedness of the human heart, the יֵצֶר לֵב ( Genesis 8:21), or, more completely, מִחְשְׁבֵתּ לֵב יֵצֵר ( Genesis 6:5; compare 1 Chronicles 28:9), and considers sin as having penetrated the center of life, from whence it contaminates its whole course. "How can ye, being evil, speak good things? for out of the abundance of the heart the mouth speaketh" ( Matthew 12:34; comp. Ecclesiastes 8:11; Psalms 73:7); and those things which come out of the heart defile the man ( Matthew 15:18). The heart is described as "deceitful (or, more properly, עָקבֹ , Crooked, the opposite of יָשָׁר straight) above all things, and desperately wicked" ( אָנוּשׁ ) ( Jeremiah 17:9); so that God alone can thoroughly sound the depths of its wickedness (compare 1 John 3:20). Hence the prayer in Psalms 139:23. In this natural state of insusceptibility for good the heart is called uncircumcised, עָרֵל ( Numbers 26:41; compare Deuteronomy 10:16; Ezekiel 44:9). Man, frightened at the manifestation of divine holiness, may take within himself the resolution of fulfilling the divine commands ( Deuteronomy 5:24); yet the divine voice complains ( Deuteronomy 5:29), "Oh that there were such a heart in them that they would fear me!" etc. Therefore the whole Revelation has for its object to change the heart of man; and its whole aim is to destroy, by virtue of its divine efficacy, the insusceptibility ("stupiditas, qua centrum animse laborat," as Roos expresses it, p. 153) and the antagonism of the heart, and to substitute for them the fear of God in the heart ( Jeremiah 32:40), so that the law may be admitted ( Jeremiah 31:33). This is the effect of the operations of the Holy Spirit, whose workings, as shown in the O.T., point to the regeneration of the heart in redemption ( Ezekiel 36:26 sq.; Ezekiel 11:19), transforming the prophets to new creatures by means of a change of heart ( 1 Samuel 10:6; 1 Samuel 10:9), and implanting a willingness to obey God's law in the pious ( Psalms 51:12-14).
(4) On the part of man, the process of salvation begins in the heart by the faith awakened by the testimony of revelation; which, as giving a new direction to the inner life, belongs entirely to the sphere of the heart, and is described as a fastening (according to the original meaning of הֶאֵַמין ), a strengthening ( האמיוֹ , Psalms 27:14; Psalms 31:24), a supporting of the heart (comp. particularly Psalms 112:7) on the ground which is God himself, the צוּד לֵבָב ( Psalms 73:26). The N.T. says in the same manner: Καρδίᾷ Πιστεύεται ( Romans 10:9-10), Πιστεύειν Ἐξ Ὅλης Τῆς Καρδίας ; faith is a Μὴ Διακρίνεσδαι Ἐν Καρδίᾷ ( Mark 1:23). God purifies the heart by faith in Christ ( Acts 15:9), for by the sprinkling of the blood of atonement the heart is rid of the bad conscience ( Hebrews 10:22; compare 1 John 3:19-21), and the love of God is shed in it by the Holy Ghost ( Romans 5:5). The same spirit also seals in the heart the assurance of being a child of God ( 2 Corinthians 1:22); the heart becomes the abode of Christ ( Ephesians 3:16), is preserved in Christ ( Colossians 3:15; Philippians 4:7), and strengthened in sanctification ( 1 Thessalonians 3:13, etc.).
When, on the contrary, man rejects the testimony of revelation, the heart becomes hardened, turns to stone ( הַקַשָׁה , Psalms 96:8; Proverbs 28:14; אַמֵּוֹ . 2 Chronicles 36:13; חַזֵּק , Exodus 4:21; כַּבֵּד , 1 Samuel 6:6), for which we find it also said that the heart is shut ( Isaiah 44:18), made fat ( Isaiah 6:10; compare Psalms 119:70). In the N. Test. we find Πωρώσις Καρδίας ( Mark 3:5; Ephesians 4:18); Σκληροκαρδία ( Matthew 19:8, etc.). The most important passage in this respect is Isaiah 6:10, where we find it particularly stated how the unsusceptible heart renders one unable to see the work of God, to hear his Word, and how this inability reacts on the heart, and renders its state incurable.
3. Finally, the question of the position the heart, as center of the spiritual life of the soul, holds in regard to the heart, considered as the center of the organic (physical) life, cannot be fully treated except in a thorough investigation of the relations between the body and soul in general. We will only remark here that the Scriptures not only draw a parallel between the body and the soul, by virtue of which the bodily actions are considered as symbols of the spiritual, but also establish the position that the soul, which is the bearer of the personality, is the same which directs also the life and actions; and thus the bodily organs, in their higher functions, become its adjuncts. Now, in view of the well-known fact that emotions and sufferings affect the physical economy for example, that the pulsations of the heart are affected by them - no one will consider it a mere figure of speech when the Psalmist says, "My heart was hot within me" ( Psalms 39:3), or Jeremiah speaks of "a burning fire shut up in his bones" ( Jeremiah 20:9; comp. Jeremiah 4:19; Jeremiah 23:9).
But there is one point worthy of special attention in Biblical anthropology, namely, the specific relation the Bible establishes between certain parts of the bodily organism and particular actions (see what Delitzsch, Biblical Psychology, § 12, 13, deduces from the Biblical signification of the
רִחֲמַים , the Liver, the Kidneys), and then the part attributed to the heart in knowledge and will, considered aside from the head and brain. It is well known that all antiquity agreed with the Biblical views in these respects. In regard to Homer's doctrine, see Nagelsbach's Homer. Theologie, p. 332 sq. We may also on this point recall the expressions cordatus, recordari, vecors, excors, etc. (see especially Cicero, Tusc. 1, 9, 18, and Plato, Phaed. c. 45, and-the commentators on these passages). As Delitzsch correctly observes, the spiritual signification of the heart cannot be traced back to t from the mere fact of its being the central organ of the circulation. The manner in which that writer has made use of the phenomena of somnambulism to explain this is deserving of due notice, yet physiology has thus far been unable to throw any light on the subject. — Oehler, in Herzog, Real-Encyklop. 6, 15 sq.
4. The heart expresses the middle of anything: "Tyre is in the heart," in the midst, "of the sea" ( Ezekiel 27:4). "We will not fear, though the mountains be carried into the heart of the sea" ( Psalms 46:2). "As Jonah was three days and three nights in the whale's belly, so shall the Son of man be three days and three nights in the heart of the earth" ( Matthew 12:40). Moses, speaking to the Israelites, says, "And the mountain burnt with fire, unto the heart of heaven;" the flame rose as high as the clouds.
To "say in one's heart" is a Hebrew expression for thinking ( Psalms 10:6; Psalms 14:1). (See Soul).
5. Of special religious importance are the following practical uses of the word:
Hardness of heart is "that state in which a sinner is inclined to and actually goes on in rebellion against God. This state evidences itself by light views of the evil of sin; partial acknowledgment and confession of it; frequent commission of it; pride and conceit; ingratitude; unconcern about the Word and ordinances of God; inattention to divine providences; stifling convictions of conscience; shunning reproof; presumption, and general ignorance of divine things."
Keeping the heart is "a duty enjoined in the sacred Scriptures. It consists, says Flavel, in the diligent and constant use and improvement of all holy means and duties to preserve the soul from sin, and maintain communion with God; and this, he properly observes, supposes a previous work of sanctification, which hath set the heart right by giving it a new bent and inclination.
1. It includes frequent observation of the frame of the heart ( Psalms 77:6).
2. Deep humiliation for heart evils and disorders ( 2 Chronicles 32:26).
3. Earnest supplication for heart purifying and rectifying grace ( Psalms 19:12).
4. A constant holy jealousy over our hearts ( Proverbs 27:14).
5. It includes the realizing of God's presence with us, and setting him before us ( Psalms 16:8; Genesis 17:1).
1. The hardest work; heart work is hard work indeed.
2. Constant work ( Exodus 17:12). 3. The most important work ( Proverbs 23:26).
This is a duty which should be attended to if we consider it in connection with,
1. The honor of God ( Isaiah 66:3).
2. The sincerity of our profession ( 2 Kings 10:31; Ezekiel 32:31-32).
3. The beauty of our conversation ( Proverbs 12:26; Psalms 45:1).
4. The comfort of our souls ( 2 Corinthians 13:5).
5. The improvement of our graces ( Psalms 63:5-6).
6. The stability of our souls in the hour of temptation ( 1 Corinthians 16:13).
The seasons in which we should more particularly keep our hearts are,
1. The time of our prosperity ( Deuteronomy 6:10; Deuteronomy 6:12).
2. Under afflictions ( Hebrews 7:5-6).
3. The time of Sion's troubles ( Psalms 46:1; Psalms 46:4).
4. In the time of great and threatening danger ( Isaiah 26:20-21).
5. Under great wants ( Philippians 4:6-7).
6. In the time of duty ( Leviticus 10:3).
7. Under injuries received ( Romans 12:17, etc.).
8. In the critical hour of temptation ( Matthew 26:41).
9. Under dark and doubting seasons ( Hebrews 12:8; Isaiah 1, 10).
10. In time of opposition and suffering ( 1 Peter 4:12-13).
11. The time of sickness and death ( Jeremiah 49:11).
The means to be made use of to keep our hearts are,
1. Watchfulness ( Mark 13:37).
2. Examination ( Proverbs 4:26).
3. Prayer ( Luke 18:1).
4. Reading God's Word ( John 5:39).
5. Dependence on divine grace ( Psalms 86:11). See Flavel, On Keeping the Heart; Jamieson, Sermons on the Heart."
International Standard Bible Encyclopedia 
hart ( לב , lēbh , לבב , lēbhābh ; καρδία , kardı́a ): The different senses in which the word occurs in the Old Testament and the New Testament may be grouped under the following heads:
1. Various Meanings
It represents in the first place the bodily organ , and by easy transition those experiences which affect or are affected by the body. Fear, love, courage, anger, Joy, sorrow, hatred are always ascribed to the heart - especially in the Old Testament; thus courage for which usually rūaḥ is used ( Psalm 27:14 ); joy ( Psalm 4:7 ); anger ( Deuteronomy 19:6 , "while his heart is hot," lēbhābh ); fear ( 1 Samuel 25:37 ); sorrow ( Psalm 13:2 ), etc.
Hence, naturally it came to stand for the man himself ( Deuteronomy 7:17; "say in thine heart," Isaiah 14:13 ).
2. Heart and Personality
As representing the man himself, it was considered to be the seat of the emotions and passions and appetites ( Genesis 18:5; Leviticus 19:17; Psalm 104:15 ), and embraced likewise the intellectual and moral faculties - though these are necessarily ascribed to the "soul" as well. This distinction is not always observed.
3. Soul and Heart
"Soul" in Hebrew can never be rendered by "heart"; nor can "heart" be considered as a synonym for "soul." Cremer has well observed: "The Hebrew nephesh ("soul") is never translated kardia ("heart").... The range of the Hebrew nephesh , to which the Greek psuchḗ alone corresponds, differs so widely from the ideas connected with psuchē , that utter confusion would have ensued had psuchē been employed in an unlimited degree for lēbh ("heart"). The Biblical lēbh never, like psuchē , denotes the personal subject, nor could it do so. That which in classical Greek is ascribed to psuchē (a good soul, a just soul, etc.) is in the Bible ascribed to the heart alone and cannot be otherwise" (Cremer, Lexicon , article "Kardia," 437ff, German edition).
4. Center of Vital Action
In the heart vital action is centered ( 1 Kings 21:7 ). "Heart," except as a bodily organ, is never ascribed to animals, as is the case sometimes with nephesh and rūaḥ ( Leviticus 17:11 , ה , nephesh ; Genesis 2:19; Numbers 16:22; Genesis 7:22 , ה , ruaḥ ). "Heart" is thus often used interchangeably with these two ( Genesis 41:8; Psalm 86:4; Psalm 119:20 ); but "it never denotes the personal subject, always the personal organ."
5. Heart and Mind
As the central organ in the body, forming a focus for its vital action, it has come to stand for the center of its moral, spiritual, intellectual life. "In particular the heart is the place in which the process of self-consciousness is carried out, in which the soul is at home with itself, and is conscious of all its doing and suffering as its own" (Oehler). Hence, it is that men of "courage" are called "men of the heart"; that the Lord is said to speak "in his heart" ( Genesis 8:21 ); that men "know in their own heart" ( Deuteronomy 8:5 ); that "no one considereth in his heart' ( Isaiah 44:19 the King James Version). "Heart" in this connection is sometimes rendered "mind," as in Numbers 16:28 ("of mine own mind," Vulgate (Jerome's Latin Bible , 390-405 ad) ex proprio corde , Septuagint ap' emautoú ); the foolish "is void of understanding," i.e. "heart" ( Proverbs 6:32 , where the Septuagint renders phrenō̇n , Vulgate (Jerome's Latin Bible , 390-405 ad) cordis , Luther "der ist ein Narr"). God is represented as "searching the heart" and "trying the reins" ( Jeremiah 17:10 the King James Version). Thus, "heart" comes to stand for "conscience," for which there is no word in Hebrew, as in Job 27:6 , "My heart shall not reproach me," or in 1 Samuel 24:5 , "David's heart smote him"; compare 1 Samuel 25:31 . From this it appears, in the words of Owen: "The heart in Scripture is variously used, sometimes for the mind and understanding, sometimes for the will, sometimes for the affections, sometimes for the conscience, sometimes for the whole soul. Generally, it denotes the whole soul of man and all the faculties of it, not absolutely, but as they are all one principle of moral operations, as they all concur in our doing of good and evil."
6. Figurative Senses
The radical corruption of human nature is clearly taught in Scripture and brought into connection with the heart. It is "uncircumcised" ( Jeremiah 9:26; Ezekiel 44:7; compare Acts 7:51 ); and "hardened" ( Exodus 4:21 ); "wicked" ( Proverbs 26:23 ); "perverse" ( Proverbs 11:20 ); "godless" ( Job 36:13 ); "deceitful and desperately wicked" ( Jeremiah 17:9 the King James Version). It defiles the whole man ( Matthew 15:19 , Matthew 15:20 ); resists, as in the case of Pharaoh, the repeated call of God ( Exodus 7:13 ). There, however, the law of God is written ( Romans 2:15 ); there the work of grace is wrought ( Acts 15:9 ), for the "heart" may be "renewed" by grace ( Ezekiel 36:26 ), because the "heart" is the seat of sin ( Genesis 6:5; Genesis 8:21 ).
7. Process of Heart Renewal
This process of heart-renewal is indicated in various ways. It is the removal of a "stony heart" ( Ezekiel 11:19 ). The heart becomes "clean" ( Psalm 51:10 ); "fixed" ( Psalm 112:7 ) through "the fear" of the Lord ( 1 Samuel 25:1 ); "With the heart man believeth" ( Romans 10:10 ); on the "heart" the power of God is exercised for renewal ( Jeremiah 31:33 ). To God the bereaved apostles pray as a knower of the heart ( Acts 1:24 - a word not known to classical writers, found only here in the New Testament and in Acts 15:8 , kardiognō̇stēs ). In the "heart" God's Spirit dwells with might ( Ephesians 3:16 , eis tón ésō ánthrōpon ); in the "heart" God's love is poured forth ( Romans 5:5 ). The Spirit of His son has been "sent forth into the heart" ( Galatians 4:6 ); the "earnest of the Spirit" has been given "in the heart" ( 2 Corinthians 1:22 ). In the work of grace, therefore, the heart occupies a position almost unique.
8. The Heart First
We might also refer here to the command, on which both the Old Testament and New Testament revelation of love is based: "Thou shalt love Yahweh thy God with all thy heart, and with all thy soul, and with all thy might" ( Deuteronomy 6:5 ); where "heart" always takes the first place, and is the term which in the New Testament rendering remains unchanged (compare Matthew 22:37; Mark 12:30 , Mark 12:33; Luke 10:27 , where "heart" always takes precedence).
9. A T erm for "Deepest"
A bare reference may be made to the employment of the term for that which is innermost, hidden, deepest in anything ( Exodus 15:8; Jonah 2:3 ), the very center of things. This we find in all languages. Compare Ephesians 3:16 , Ephesians 3:17 , "in the inward man," as above.
Kitto's Popular Cyclopedia of Biblial Literature 
All the phrases, more or less metaphorical, in which this word occurs, are rendered intelligible, without detailed examples, when we are told that the heart was, among the Hebrews, regarded poetically not only as the seat of the passions and emotions, as of love, pleasure, and grief, but also of the intellectual faculties—the mind, the understanding. In the original Scriptures, as well as in the English and other translations, the word 'heart' therefore, constantly occurs where 'mind' is to be understood, and would be used by a modern English writer. We say modern, because the ancient usage of the English word 'heart' was more conformable than the present to that of the Hebrews.
- Heart from Hastings' Dictionary of the New Testament
- Heart from Baker's Evangelical Dictionary of Biblical Theology
- Heart from Hastings' Dictionary of the Bible
- Heart from Holman Bible Dictionary
- Heart from Vine's Expository Dictionary of OT Words
- Heart from Charles Buck Theological Dictionary
- Heart from Wilson's Dictionary of Bible Types
- Heart from Bridgeway Bible Dictionary
- Heart from King James Dictionary
- Heart from Watson's Biblical & Theological Dictionary
- Heart from Webster's Dictionary
- Heart from Easton's Bible Dictionary
- Heart from People's Dictionary of the Bible
- Heart from Morrish Bible Dictionary
- Heart from Vine's Expository Dictionary of NT Words
- Heart from Fausset's Bible Dictionary
- Heart from Hawker's Poor Man's Concordance And Dictionary
- Heart from Cyclopedia of Biblical, Theological and Ecclesiastical Literature
- Heart from International Standard Bible Encyclopedia
- Heart from Kitto's Popular Cyclopedia of Biblial Literature