Bp. of Mopsuestia, biblical commentator, author of theological works and homilies. Little is known of Theodore’s early years, except that he studied with the pagan rhetor Libanius in Antioch and probably knew Diodore of Tarsus and John Chrysostom. That he wavered from his ascetic endeavors and needed to be rebuked by John Chrysostom rests entirely on the identification of Theodore with the addressee of John’s letter ‘To the fallen Theodore’, an identification Theodore’s later opponents were eager to make, but for which there is very little evidence. In 392 Theodore became bp. of Mopsuestia, north of Antioch, a position that he held until his death in 428. He died in peace with the Church.

Following the deposition of Nestorius at the Council of Ephesus (431), Theodore began to be seen as the originator of Nestorianism. Rabbula, bp. of Edessa and follower of Cyril of Alexandria, anathematized Theodore’s works in 432 and ordered them to be burned. Although Theodore was somewhat rehabilitated when at the Council of Chalcedon (451) Hiba’s letter to Mari the Persian was read, which spoke about Theodore in positive terms, later he again was targeted for his allegedly Nestorian views, which eventually led to his condemnation at the Fifth Ecumenical Council at Constantinople (553).

Theodore’s works started being translated into Syriac perhaps even during his life, or shortly after his death. They became very popular in Edessa, in particular at the School of Edessa, even though the followers of Bp. Rabbula (d. 435) strongly rejected them. They had a decisive influence on those theologians who in the second half of the 5th cent. left Edessa and founded a new School in Nisibis, within the Persian Empire. The theology of the late-5th-cent. councils of the Ch. of E. primarily reflects the views of Theodore. He saw a clear distinction between the divine and human natures in Christ: the Word of God indwelt the assumed Man, whereby the two came together in one ‘person’ (Greek prosōpon, Syr. parṣopā), serving as one object of veneration. In his biblical interpretation Theodore, a major representative of the so-called School of Antioch, saw the biblical text primarily in its historical context. Only rarely, and under strict conditions, was he willing to admit NT references or Christological typologies within the OT. His main interpretative framework was God’s salvation plan, seen as a process of education throughout history, leading up to the NT realities and the hereafter, whereby each individual phase is respected in its own right. Theodore rejected the idea of double meanings in the biblical message, which he saw as the major shortcoming of allegorical interpretation, which he connected with Philo of Alexandria and Origen.

While only small portions of Theodore’s works survive in Greek (with the exception of the commentary on the Twelve Prophets, which survives in its entirety), E.-Syr. tradition has preserved a collection of 16 catechetical homilies (ed. Tonneau and Devreesse), biblical commentaries dealing with both OT and NT (ed. Sachau, Vosté, Tonneau, Jansma, and Van Rompay), and a disputation with the followers of Macedonius (ed. Nau). One major theological work, on the Incarnation, existed in the library of Msgr. Addai Scher in Siirt, Turkey, but it was lost during the First World War. Excerpts and quotations from many more of Theodore’s works can be found in a great number of E.-Syr. writings, while he is a much quoted authority in all E.-Syr. biblical commentaries, often introduced with the simple term mpaššqānā, i.e., the Interpreter. One of the Eucharistic Anaphoras in use in the Ch. of E. is attributed to him.