THEODORE'TUS (Gr. iheodoretos, God-bestowed), a celebrated church historian and theological writer, was born at Antioch about the year 393, and received his name from the circumstance of his being supposed to have been granted as the fruit of earnest prayer, to his parents, who had long been childless. He was educated from early childhood in a monastery, where, among his fellow pupils, were Nestorius and John of Antioch, both afterward. celebrated in the controversy which takes its name from the former. He was admitted among the clergy of Antioch; and at a comparatively early age became bishop of Cyrus, a city of Syria. His zeal and eloquence were the theme of universal praise, and his success in bringing unbelievers and heretics to the church was almost unprecedented. Iu the controversies on the subject of Nestorius and his doc trines, which followed the condemation pronounced by the council of Ephesus in 431, Theodoretus for a time took a warm and active interest. The party of Nestorius was with difficulty brought to an accommodation with Cyril of Alexandria, in virtue of which the condemnation of Nestorius by the council was acquiesced in by John, bishop of Antioch. For a time Theodoretus dissented from this condemnation of Nestorius; and lie not only expressed these sentiments in a letter addressed to Nestorius himself, but also wrote formally against the celebrated anathemas of Cyril directed against Nestorianism. But he afterward saw the necessity of yielding, and concurred in the deposition of those bishops whb still persisted in their rejection of the council of Ephesus. Nevertheless, he by no means fully accepted the views of Cyril; and when, on Cyril's death, the opposition to Nestoriauism began to develop, under the turbulent partisanship of his successor in the see of Alexandria, Dioscorus, into the contrary error of Eutychianism. Theodoretus endeavored to induce Dioscorus to abandon his extreme opinions. Failing in the attempt, Theodoretus composed the work which has often figured in modern controversy, on account of the well known passage as to the change of the eucharistic elements which it contains, entitled "Eranistes or the Many-shaped."
This work was regarded by Dioscorus as a renewal of the Nestorian error, and he accused Theodoretus to Domnus, the new patriarch of Antioch, of that heresy. Theo doretus replied with great moderation; but Dioscorus persisted; and having engaged the imperial court ou his side, succeeded in obtaining from the emperor Theodosius II. an order confining Theodoretus within the limits of his own diocese. Meanwhile, the Eutychian controversy reached its height, and Eutyches (q.v.) having been first con demned by Flavian, bishop of Constantinople, in a synod held in 448, was afterward absolved in the celebrated robber-council of Ephesus, under Dioscorus in 449. The latter council not only excluded Theodoretus from its sittings, but formally deposed him from his see; whereupon he was compelled to retire to the monastery at Antioch in which he had received his first education. All this, however, was reversed by the general council of Chalcedon, in 451. Theodoretus did not very long survive his restor ation. He died about the year 457. His works fill four volumes folio, reprinted in 10 parts 8vo, by Schulze (Halle, 1768-74), and consist of commentaries on many books of the Old Testament and the whole of St. Paul's Epistles; a History of the Church, from 325 to 429 A.D., iu five books; Religious .History, being the lives of the so-called fathers of the desert, a series of most curious and interesting pictures of early ascetic life; the grantees. a dialogue against Eutychianism; A Concise History of Heresies, together with orations and a large number of letters. Of these works, his History of the Church is by far the best known, as well as the most important and interesting. See Schulze's edition of Theodoreti Cyrensis Opera.