Hastings' Dictionary of the Bible 
GEHENNA . A word derived from Ge-Hinnom , the valley on the west of Jerusalem. In this valley it is possible that Molech and Tammuz were worshipped ( 2 Kings 23:18 , 2Ch 28:3; 2 Chronicles 33:6 , Jeremiah 7:31; Jeremiah 32:35 ). The recollection of this terrible worship gave to the valley a sinister character, and led to its being defiled by Josiah ( 2 Kings 23:6; 2 Kings 23:10 ), for the purpose of preventing these rites. Thereafter it became the place for the burning of the refuse of the city, along with dead animals and the bodies of criminals. It was natural, therefore, that the name should become a synonym of hell (cf. Matthew 5:29; Matthew 10:28 ). In its eschatological force Gehenna was the place of punishment. It generally was conceived of as being under the earth, but it was very much vaster in extent than the earth. It was believed to be filled with fire intended for the punishment of sinners, who apparently went there immediately after death. Late Rabbinic thought would seem to imply that men who are neither great saints nor great sinners might be purified by the fire of Gehenna. Only those who had committed adultery or shamed or slandered their neighbours were believed to be hopelessly condemned to its fires, while the Jews were not to be permanently injured by them. According to the later belief, Gehenna was to be destroyed at the final consummation of the age. There is no clear evidence that Gehenna was regarded as a place for the annihilation of the wicked, although there are some passages which give a certain support to this opinion. No systematic eschatological statement has, however, been preserved for us from Jewish times, much less one which may be said to represent a general consensus of opinion. The NT writers employ the word in its general force as a synonym for the idea of endless punishment for sinners, as over against ‘heaven’ the synonym of endless bliss for those who have enjoyed the resurrection. They attempt, however, no description of suffering within its limits further than that implied in the figures of fire and worms.
Holman Bible Dictionary 
Joshua 15:8 Joshua 18:16 2 Chronicles 33:6 Jeremiah 32:35
The New Testament uses Gehenna to speak of the place of final judgment. Jesus warned that those who called another, “Thou fool,” faced the danger of the fire of Gehenna ( Matthew 5:22 ). He taught it is better to destroy a part of one's body than to have one's whole body thrown into Gehenna ( Matthew 5:29; Matthew 18:9; Mark 9:43 ,Mark 9:43, 9:45 ,Mark 9:45, 9:47 ). In Gehenna worms are constantly at work in a fiery environment that burns forever ( Mark 9:48 ). Only God can commit people to Gehenna and so is the only One worthy of human fear ( Matthew 10:28; Luke 12:5 ). Jesus condemned the Pharisees for making converts but then turning them into sons of Gehenna, that is, people destined for hell ( Matthew 23:15 ). He scolded the Pharisees, warning they had no chance to escape Gehenna through their present practices ( Matthew 23:33 ). For many people James warned that they could not control their tongues that Gehenna had set on fire ( James 3:6 ). See Hell .
Easton's Bible Dictionary 
2 Chronicles 28:3 33:6 Jeremiah 7:31 19:2-6 Matthew 5:22,29,30 10:28 18:9 23:15,33 Mark 9:43,45,47 Luke 12:5 James 3:6
Baker's Evangelical Dictionary of Biblical Theology 
American Tract Society Bible Dictionary 
See Hinnom .
Morrish Bible Dictionary 
Hastings' Dictionary of the New Testament 
International Standard Bible Encyclopedia 
gē̇ - hen´a ( γεέννα , geénna (see Grimm-Thayer, under the word)): Gehenna is a transliteration from the Aramaic form of the Hebrew gē - hinnōm , "valley of Hinnom." This latter form, however, is rare in the Old Testament, the prevailing name being "the valley of the son of Hinnom." Septuagint usually translates; where it transliterates the form is different from Gehenna and varies. In the New Testament the correct form is Geénna with the accent on the penult, not Géenna ̌ . There is no reason to assume that Hinnom is other than a plain patronymic, although it has been proposed to find in it the corruption of the name of an idol ( Eb , II, 2071). In the New Testament (King James Version margin) Gehenna occurs in Matthew 5:22 , Matthew 5:29 , Matthew 5:30; Matthew 10:28; Matthew 18:9; Matthew 23:15 , Matthew 23:33; Mark 9:43 , Mark 9:15 , Mark 9:47; Luke 12:5; James 3:6 . In all of these it designates the place of eternal punishment of the wicked, generally in connection with the final judgment. It is associated with fire as the source of torment. Both body and soul are cast into it. This is not to be explained on the principle that the New Testament speaks metaphorically of the state after death in terms of the body; it presupposes the resurrection. In the King James Version and the Revised Version (British and American) Gehenna is rendered by "hell" (see Eschatology Of The New Testament ). That "the valley of Hinnom" became the technical designation for the place of final punishment was due to two causes. In the first place the valley had been the seat of the idolatrous worship of Molech, to whom children were immolated by fire ( 2 Chronicles 28:3; 2 Chronicles 33:6 ). Secondly, on account of these practices the place was defiled by King Josiah ( 2 Kings 23:10 ), and became in consequence associated in prophecy with the judgment to be visited upon the people ( Jeremiah 7:32 ). The fact, also, that the city's offal was collected there may have helped to render the name synonymous with extreme defilement. Topographically the identification of the valley of Hinnom is still uncertain. It has been in turn identified with the depression on the western and southern side of Jerusalem, with the middle valley, and with the valley to the E. Compare EB , II, 2071; DCG , I, 636; RE 3, VI.
Cyclopedia of Biblical, Theological and Ecclesiastical Literature 
( Γεέννα , A.V. invariably "hell"), the Greek representative of גֵּיאּהנֹּם Joshua 15:8; Neb. xi) 30 (rendered by the Sept. Γαιέννα , Joshua 18:16); more fully, גֵּי בֶןאּהַנֹּם or בְנֵיאּה ( 2 Kings 23:10; 2 Chronicles 28:3; 2 Chronicles 33:6; Jeremiah 19:2), the "valley of Hinnone," or "of the son" or children of Hinnom," a deep narrow glen to the sosth of Jerusalem, where, after the introduction of the worship of the fire-gods by Ahaz, the idolatrous Jews offered their children to Moloch ( 2 Chronicles 28:3; 2 Chronicles 33:6; Jeremiah 7:31; Jeremiah 19:2-6). In consequence of these abominations the valley was polluted by Josiah ( 2 Kings 23:10); subsequently to which it became the common lay-stall of the city, where the dead bodies of criminals, and the carcasses of animals, and every other kind of filth was cast, and, according to late and some, what questionable authorities, the combustible portion consumed with fire. From the depth asnd narrowness of thee gorge, and, perhaps, its ever-burning fires, as well as from its being the receptacle of all sorts of putrefying matter, and all that defiled the holy city, it became in later times the image of the place of everlasting punishnent, "where their worm dieth not, and the fire is not quenched;" in which the Talmudists placed the mouth of bell: "There are two palm-trees in the valley of Hinnom, between which a smoke ariseth ... and this is the door of Gehenna" (Talmud, quoted by Barclay, City of Great King, page 90; Lightfoot, Centur. Chorograph. Matt. proem. 2:200). The Mohammedans still use the term as the current designation of the infernal regions (see D'Herbelot, Bibliothique Orient. s.v. Gehennen). In this sense the word is used by our Lord, Matthew 5:29-30; Matthew 10:28; Matthew 23:15; Matthew 23:33; Mark 9:43; Luke 12:5; and with the addition Τοῦ Πυρός , Matthew 5:22; Matthew 18:9; Mark 9:47; and by James 3:6. (See Valley Of Hinnom); (See Tophet); (See Hell).
The Nuttall Encyclopedia 
The valley of Hinnom, on the S. of Jerusalem, with Tophet ( q. v .) at its eastern end; became the symbol of hell from the fires kept burning in it night and day to consume the poisonous gases of the offal accumulated in it.
- Gehenna from Hastings' Dictionary of the Bible
- Gehenna from Holman Bible Dictionary
- Gehenna from Easton's Bible Dictionary
- Gehenna from Baker's Evangelical Dictionary of Biblical Theology
- Gehenna from American Tract Society Bible Dictionary
- Gehenna from Morrish Bible Dictionary
- Gehenna from Hastings' Dictionary of the New Testament
- Gehenna from International Standard Bible Encyclopedia
- Gehenna from Cyclopedia of Biblical, Theological and Ecclesiastical Literature
- Gehenna from The Nuttall Encyclopedia