Watson's Biblical & Theological Dictionary 
a sect of the first two or three centuries; but it is not certain whether they received their name from a leader of the name of Ebion, (whom Dr. Lardner considers as a disciple of Cerinthus,) or from the meaning of the Hebrew word ebion, which implies poverty; and if the latter, whether they assumed the name, as affecting to be poor, like the Founder of Christianity; or whether it was conferred on them by way of reproach, as being of the lower orders. The use of the term, also, according to Dr. Horsley, was various and indefinite. Sometimes it was the peculiar name of those sects that denied both the divinity of our Lord, and his miraculous conception. Then its meaning was extended, to take in another, party; who admitted the miraculous conception of Jesus, but still denied his divinity, and questioned his previous existence. At last, it seems, the Nazarites, whose error was rather a superstitious severity in their practice, than any deficiency in their faith, were included by Origen in the infamy of the appellation. Dr. Priestly, claiming the Ebionites as Jewish Unitarians, considers the ancient Nazarenes, that is, the first Jewish converts, as the true Ebionites; these, he thinks, were called Nazarenes, from their attachment to Jesus of Nazareth; and Ebionites, from their poor and mean condition, just as some of the reformers were called Beghards, or beggars. The Doctor cites the authorities of Origen and Epiphanius, to prove that both these denominations related to the same people, differing only, like the Socinians, in receiving or rejecting the fact of the miraculous conception; and neither, as he assures us, were reckoned heretics by any writers of the two first centuries. To this Dr. Horsley replies, that both Jews and Heathens called the first Christians Nazarenes, in allusion to the mean and obscure birthplace of their Master, Jesus of Nazareth, Matthew 2:23; Acts 10:38; but insists, and answers every pretended proof to the contrary, that the term Nazarenes was never applied to any distinct sect of Christians before the final destruction of Jerusalem by Adrian. Dr. Semler, a German writer, gives the following opinion: "Those who more rigidly maintained the Mosaic observances, and who were numerous in Palestine, are usually called Ebionites and Nasaraeans. Some believe that they ought not to be reckoned heretics; others think that they were united in doctrine, differing only in name; others place them in the second century. It is of little consequence whether we distinguish or not the Nazarenes, or Nazaraeans from the Ebionites. It is certain that both these classes were tenacious of the Mosaic ceremonies, and more inclined to the Jews than to the Gentiles, though they admitted the Messiahship of Jesus in a very low and Judaizing manner. The Ebionites held in execration the doctrine of the Apostle Paul." Dr. J. Pye Smith, who quotes this passage from Dr. Semler, adds, "Such, it is apprehended, on grounds of reasonable probability, was the origin of Unitarianism; the child of Judaism misunderstood, and of Christianity imperfectly received."
2. On this controversy, great light has, however, been since thrown by Dr. Burton. It is well known to those who have studied the Unitarian controversy, that it has been often asserted that the Cerinthians and Ebionites were the teachers of genuine Christianity, and that the doctrine of Christ's divinity, and of universal redemption through his blood, were the inventions of those who corrupted the preaching of the Apostles. If this were so, we must convict all the fathers, not merely of ignorance and mistake, but of deliberate and wilful falsehood. To suppose that the fathers of the second century were ignorant of what was genuine and what was false in Christianity, would be a bold hypothesis; but if Irenaeus, the disciple of Polycarp, asserted, as a matter of fact, that St. John wrote his Gospel to refute the errors of Cerinthus, it is idle, or something worse, to say that Irenaeus did not know for certain if the fact was really so. As far, then, as the testimony of the fathers is concerned, the Cerinthians and Ebionites were decidedly heretics. The Unitarians, on the other hand, maintain that the Ebionites were the true and genuine believers; and it is easy to see that the preference was given to these teachers, because they held that Jesus was born of human parents. Never, I conceive, was there a more unfortunate and fatal alliance formed than that between the Ebionites and modern Unitarians. We find the Ebionites referred to, as if they agreed in every point with the Socinian or Unitarian creed; and yet it may almost be asserted, that in not one single point do their sentiments exactly coincide. If a real Ebionite will declare himself, we are not afraid to meet him. Let him avow his faith; let him believe of Christ as Ebion or Cerinthus taught; let him adopt the ravings of the Gnostics; we shall then know with whom we have to combat; we may gird on the sword of Irenaeus, and meet him in the field. But let him not select a few ingredients only from the poison; let him not take a part only of their infatuated system. If he will lean on that broken reed, let him talk no more of Ebion or Cerinthus only; but let him say boldly, either that the Gnostics agreed with the Apostles, or that the Gnostics preached the true Gospel, while the Apostles were in error.
3. We can hardly suppose the Unitarians to be ignorant that the Ebionites and Cerinthians were a branch of the Gnostics. If the fact be denied, the whole of this discussion might as well at once be closed. We know nothing of Cerinthus and Ebion, but from the writings of the fathers. If it had not been for them, we should never have known that these persons believed Jesus to be born of human parents: the same fathers unanimously add, that in this point they differed from the preceding Gnostics, though agreeing with them on other points. If we are to receive the testimony of the fathers in one particular, but to reject it in every other, I need not say that argument is useless. But the fact can never be denied nor evaded. The Cerinthians, to whom some Unitarians have appealed, did not ascribe the creation of the world to God, but to an inferior being. Like the rest of the Gnostics, who engrafted that philosophy on Judaism, the Cerinthians and Ebionites retained some of the Jewish ceremonies, though they rejected some of the Jewish Scriptures. Many of them taught that the restraints of morality were useless; and the Cerinthians, it is well known, promised to their followers a millennium of sensual indulgence. With respect to their notions concerning Christ, it is true that they believed Jesus to be born of human parents; and this fact is referred to, as if it proved the falsehood of what is called the miraculous conception of Jesus. But it is plain that this tenet is mentioned by the fathers, as being opposed to that of the other Gnostics, who held that the body of Jesus was an illusive phantom. Such had hitherto been the belief of all the Gnostics. But Cerinthus and Ebion, who were perhaps more rational in their speculations, and who lived after the publication of the three first Gospels, could not resist the evidence that Jesus was actually born, and that he had a real, substantial body. This is the meaning of the statement, that Cerinthus and Ebion believed Jesus to be born of human parents. It shows that they were not Docetae. But because there were other Gnostics who were more irrational and visionary than themselves, we are not immediately to infer that their own notion concerning the birth of Christ was the true one. They believed, at least, many of them believed, that Jesus was born in the ordinary way; that Joseph was his parent as well as Mary. But they could hardly help believing so; for they agreed with all the Gnostics in thinking (though it might seem as if this point had been forgotten) that Jesus and Christ were separate persons: they believed, as I have already stated, that Christ descended upon Jesus at his baptism, and quitted him before his crucifixion. They were therefore almost compelled to believe that Jesus, who was wholly distinct from Christ, had nothing divine in his nature, and nothing miraculous in his birth; in the same manner that they believed that the death of Jesus, from whom Christ had then departed, was like the death of any ordinary mortal, and that no atonement was made by it. But are we on these grounds to reject the miraculous conception and the atonement of Christ? Or are the Unitarians to quote these Gnostics as holding the human nature of Jesus, and to forget that by Jesus they meant a person wholly different from Christ?
4. We are told, indeed, that the first part of St. Matthew's Gospel is spurious, because the Ebionites rejected it. Undoubtedly they did. They read in it that Jesus Christ was born, not Jesus only; and that he was born of a virgin. They therefore rejected this part of St. Matthew's Gospel; or rather, by mutilating and altering the whole of it, they composed a new gospel of their own to suit their purpose; and yet this is the only authority which is quoted for rejecting the commencement of St. Matthew's Gospel. The fact, that some even of the Ebionites believed the miraculous conception, speaks infinitely more in favour of the genuineness of that part of the Gospel, and of the truth of the doctrine itself, than can be inferred on the contrary side from those who denied the doctrine, and mutilated the Gospel. Those other Ebionites appear in this respect to have agreed with the first Socinians, and to have held that Jesus was born of a virgin, though they did not believe in his preexistence or divinity. But the miraculous conception was so entirely contrary to all preconceived opinions, and the more simple doctrine of the other Ebionites and Cerinthians was so much more suited to the Gnostic system, which separated Jesus from Christ, that the evidence must have been almost irresistible, which led one part of the Ebionites to embrace a doctrine contrary to all experience, contrary to the sentiments of their brethren, and hardly reconcilable with other parts of their own creed. The testimony, therefore, of these Ebionites, in favour of the miraculous conception, is stronger, perhaps, than even that of persons who received the whole of the Gospel, and departed in no points from the doctrine of the Apostles. If the Apostles had preached, according to the statement of the Unitarians, that Jesus Christ was a mere human being, born in the ordinary way, what could possibly have led the Gnostics to rank him immediately with their AEons, whom they believed to have been produced by God, and to have dwelt with him from endless ages in the pleroma? There literally was not one single heretic in the first century, who did not believe that Christ came down from heaven: they invented, it is true, various absurdities to account for his union with the man Jesus; but the fair and legitimate inference from this fact would be, that the Apostles preached that in some way or other the human nature was united to the divine. So far from the Socinian or Unitarian doctrine being supported by that of the Cerinthians and Ebionites, I have no hesitation in saying, that not one single person is recorded in the whole of the first century who ever imagined that Christ was a mere man. It has been observed, that one branch of the Ebionites resembled the first Socinians, that is, they believed in the miraculous conception of Jesus, though they denied his preexistence; but this was because they held the common notion of the Gnostics, that Jesus and Christ were two separate persons; and they believed in the preexistence and divine nature of Christ, which Socinus and his followers uniformly denied.
Charles Buck Theological Dictionary 
Ancient heretics, who rose in the church in the very first age thereof, and formed themselves into a sect in the second century, denying the divinity of Jesus Christ. Origen takes them to have been so called from the Hebrew word ebion, which in that language signifies poor; because, says he, they were poor in sense, and wanting understanding. Eusebius, with a view to the same etymology, is of opinion they were thus called, as having poor thoughts of Jesus Christ, taking him for no more than a mere man. It is more probable the Jews gave this appellation to the Christians in general out of contempt; because, in the first times, there were few but poor people that embraced the Christian religion. The Ebionites were little else than a branch of the Nazarenes; only that they altered and corrupted, in many things, the purity of the faith held among the first adherents to Christianity. for this reason, Origen distinguishes two kinds of Ebionites in his answer to Celsus; the one believed that Jesus Christ was born of a virgin; and the other, that he was born after the manner of other men. The first were orthodox in every thing, except that to the Christian doctrine they joined the ceremonies of the Jewish law, with the Jews, Samaritans, and Nazarenes; together with the traditions of the Pharisees.
They differed from the Nazarenes, however, in several things, chiefly as to what regards the authority of the sacred writings; for the Nazarenes received all for Scripture contained in the Jewish canon; whereas the Ebionites rejected all the prophets, and held the very names of David, Solomon, Isaiah, Jeremiah, and Ezekiel, in abhorrence. They also rejected all St. Paul's epistles, whom they treated with the utmost disrespect. They received nothing of the Old Testament but the Pentateuch. they agreed with the Nazarenes, in using the Hebrew Gospel of St. Matthew, otherwise called the Gospel of the twelve apostles; but they corrupted their copy in abundance of places; and particularly had left out the genealogy of our Saviour, which was preserved entire in that of the Nazarenes, and even in those used by the Cerinthians. Besides the Hebrew Gospel of St. Matthew, the Ebionites had adopted several other books under the titles of St. James, John, and the other apostles; they also made use of the travels of St. Peter, which are supposed to have been written by St. Clement; but had altered them so, that there was scarce any thing of truth left in them. they even made that saint tell a number of falsehoods, the better to authorize their own practices.
Heresies of the Church Thru the Ages 
(possibly Aramean, Ebionia , poor men)
Term used to designate two early Christian sects infected with Judaistic and Gnostic errors.
(1) Judaistic Ebionites upheld the observance of the Jewish Law; denied the Divinity and virgin birth of Christ; considered Saint Paul an apostate; and used only a Gospel according to Saint Matthew.
(2) Ebionite Gnostics taught that matter is external, and an emanation of the Deity, that it constitutes, as it were, God's body. Creation, therefore, is but the transformation of preexisting material. God thus "creates" the Universe by the instrumentality of His wisdom. They also held that the universe is divided into two realms, that of good and that of evil. The Son of God rules over the former, and the Prince of Evil over the latter. Both teachings were confined to the East and made no definite impression upon the philosophy of their time. Nothing is known of their founders.
Cyclopedia of Biblical, Theological and Ecclesiastical Literature 
a sect of Judaizing Christians who received the doctrines of the Gospel very partially, and denied the divine nature of Christ. They do not appear to have been at any time numerous, and it is doubtful whether they ever obtained such consistency as to have a definite creed.
1. The Name . — The name is derived from the Hebrew אֶבְיוֹן , Poor. This term was anciently applied in derision to Christians in general (Epiphanius, adv. Haer. 29:1), and came later to designate Jewish Christians (Origen, Cont. Celsum, 2:1). First (Lexicon, s.v.) makes the derivation refer to Matthew 5:3 making "Ebionites" equivalent to "oppressed pious exiles" ( Isaiah 25:4). Eusebius (Hist. Ecclesiastes in, 27) fancifully derives the name from "the poverty and meanness of the Elbionite doctrine concerning Christ." Tertullian (De Praescrip. Haeret. c. 33) derives it from a founder, Edion, who maintained the authority of the Jewish law, and rejected the miraculous conception and divine nature of spirit. The derivation first above given is now generally adopted.
2. History . — Dorner (Person Of Christ, Edinb. translated 1:189 sq.) traces the Ebionitish tendency as far back as the Epistle to the Hebrews. "From that zeal for the law with which Paul had to contend, the Judaizing spirit was led not at first to impeach the Christology, but rather the Soteriology, or the work of Christ. But the consequence of the legal stand-point soon showed itself. The party which the Epistle to the Hebrews had in view must have over-estimated the law of the O.T. regarding holy times, places, acts, and persons alike, and have been wanting in the Christian knowledge which knows how to secure to the O.T. its abiding significancy, which it has as a divine institute without imperiling the newness and conclusive completeness of Christianity." Epiphanius traces the origin of Ebionitism to the Christians who fled to Pella after the destruction of Jerusalem, A.D. 66 (adv. Hoer. 29:1). According to Hegesippus (Hist. Ecclesiastes 4:22), one Thebutis, at Jerusalem, about the beginning of the second century, "began to corrupt the Church secretly on account of his not being made a bishop." "We find the sect of the Ebionites in Palestine and the surrounding regions, on the island of Cyprus, in Asia Minor, and even in Rome. Though it consisted mostly of Jews, Gentile Christians also sometimes attached themselves to it. It continued into the fourth century, but at the time of Theodoret was entirely extinct. It used a Hebrew Gospel, now lost, which was probably a corruption of the Gospel of Matthew" (Schaff, Church History, 1, § 68, page 214).
3. Doctrines. — Dr. Schaff sharply distinguishes Ebionism from Gnosticism as follows: "Ebionism is a Judaizing, pseudo-Petrine Christianity, or a Christianizing Judaism; Gnosticism is a paganizing or pseudo-Pauline Christianity, or a pseudo-Christian heathenism. The former is a particularistic contraction of the Christian religion; the latter a vague expansion of it" (Church History, § 67). According to the same writer, "the characteristic marks of Ebionism in all its forms are, degradation of Christianity to the level of Judaism, the principle of the universal and perpetual validity of the Mosaic law, and enmity to the apostle Paul. But, as there were different sects in Judaism itself, we have also to distinguish at least two branches of Ebionism, related to each other, as Pharisaism and Essenism, or, to use a modern illustration, as the older deistic and the speculative pantheistic rationalism in Germany, or the two schools of Unitarianism in England and America.
1. The common Ebionites, who were by far the more numerous, embodied the Pharisaic legal spirit, and were the proper successors of the Judaizers opposed in the epistle to the Galatians. Their doctrine may be reduced to the following propositions:
(a.) Jesus is, indeed, the promised Messiah, the son of David, and the supreme lawgiver, yet a mere man, like Moses and David, sprung by natural generation from Joseph and Mary. The sense of his Messianic calling first arose in him at his baptism by John, when a higher spirit joined itself to him. Hence Origen compared this sect to the blind man in the Gospel who called to the Lord without seeing him, 'Thou son of David, have mercy on me!'
(b.) Circumcision and the observance of the whole ritual law of Moses are necessary to salvation for all men.
(c.) Paul is an apostate and heretic, and all his epistles are to be discarded. The sect considered him a native heathen, who came over to Judaism in later life from impure motives.
(d.) Christ is soon to come again to introduce the glorious millennial reign of the Messiah, with the earthly Jerusalem for its seat.
2. The second class of Ebionites, starting with Essenic notions, gave their Judaism a speculative or theosophic stamp, like the errorists of the Epistle to the Colossians. They form the stepping-stone to Gnosticism.
Among these belong the Elkesaites" (Schaff, Ch. Hist. 1, § 68, 214 sq.). The pseudo-Clementine homilies teach a speculative form of Ebionism, essentially Judaizing in spirit and aim [ (See Clementines), 2, page 383]; and compare Schaff, Ch. History, 1, § 69; Dorner, Person Of Christ, Edinb. transl., page 203 sq.).
4. Ebionism has reappeared, since the Reformation, in Socinianism (q.v.), and in the other forms of what is called Unitarianism (q.v.). Some Unitarian writers have undertaken to show that Ebionism was the original form of Christian doctrine, and that the Church doctrine as to the person of Christ was a later development; so Priestley, in his History Of The Corruptions Of Christianity (Birmingham, 1782). Bishop Horsley replied to Priestley in his Charge To The Clergy Of St. Albans (1783), and in other tracts, collected in Tracts In Controversy With Dr. Priestley (Dundee, 1812, 3d ed.). Horsley, in this controversy, made use of Bull's learned treatment of the subject in his reply to Zwicker (see Bull, On the Trinity, Oxford, 1855, 3 vols.: 1:116; 2:376; 3:175 et al. See also Waterland, Works, Oxf. 1843, 6 vols.: 3:554 sq.). A far abler advocate of the Socinian view is Baur, in his Christenthum d. drei erstess Jahrhunderte; Lehre v.d. Dreieinigkeit Gottes; Dogmengeschichte, etc. Baur's position is clearly stated, and refuted by professor Fisher (Am. Presb. and Theolog. Rev. October 1864, art. 1). "Baur agrees with the old Socinians in the statement that the Jewish Christianity of the apostolic age was Ebionite. But, unlike them, he holds that we find within the canon a great departure from, and advance upon, this humanitarian doctrine of Christ's person. He professes to discover in the New Testament the consecutive stages of a progress which, beginning with the Unitarian creed terminates in the doctrine of Christ's proper divinity. There occurred at the end, or before the end, of the apostolic age, a reaction of the Jewish Christianity, which with Baur is identical with the Judaizing or Ebionite element; and this type of Christianity prevailed through the larger part of the second century." (See Fisher, 1. c., for a criticism of this view, and for a brief but luminous sketch of Ebionism. On the other side, see N. Amer. Rev. April, 1864, page 569 sq.).
Literature. — See, besides the works already cited, Irenaeus, Har. 1:26 (Ante-Nicene Library, verse 97); Gieseler, Ueber die Nazarder und Ebioniten, in Archiv fur A.&N. Kircheng., 4:279 sq. (Leipsig, 1820); Mosheim, Comnmentaries, 1:220, 400; Neander, Church Hist. 1:344; 350; Schliemann, Die Clementinen (Hamb. 1844), page 362 sq.; Herzog, Real- Esacyklopadie, 3:621 sq.; Martensen, Dogmatics (Edinburgh, 1866), § 128; Shedd, History of Doctrines, 1:106 sq.; Burton, Ecclesiastes History, Lect. 11; Burton, Bampton Lectures (Oxford, 1829), notes 73-84.
The Nuttall Encyclopedia 
A sect that in the 2nd century sought to combine Judaism and the hopes of Judaism with Christianity, and rejected the authority of St. Paul and of the Pauline writings; they denied the divinity of Christ, and maintained that only the poor as such were the objects of salvation.