The heresiarch Nestorius (ca. 389-ca. 453) was patriarch of Constantinople from 428 to 431. He was the "founder" of the Nestorian Church.
Nestorius was probably born about 389 in Germanicia in the province of Cilicia. During his youth he moved to Syrian Antioch, where he received the major portion of his education. He is first seen with historical certainty as a monk in the monastery of Eupreprius near Antioch. He seems to have been a popular and learned preacher—fiercely orthodox—and a writer of considerable theological acumen.
In 428 Nestorius was called to be patriarch of Constantinople. The imperial city had for years been in the throes of theological strife, so it seemed best to the emperor, Theodosius II, to call someone in from outside. Upon his arrival in Constantinople, Nestorius immediately exhibited his zeal by his attacks upon heresy and paganism. He moved about as befits a bishop, little realizing that his role as protector of the faith would soon be radically altered.
By virtue of his Antiochene training and background, Nestorius was bound to differ theologically with the tenor of thought common to Alexandria; and because of his present position, he was bound to be in conflict politically with that same city. Both of these feuds had existed for some time, and Nestorius's episcopate fanned the flames of the controversy. The difficulty began when one of the monks that Nestorius had brought with him from Antioch—a certain Anastasius—preached a sermon on the Virgin Mary denying that she should be referred to as theotokos, or God-bearer. The sermon offended many pious Christians and caused such a stir that Nestorius embarked upon a series of sermons himself, supporting Anastasius' views and developing them theologically.
World of these events soon reached Cyril, the patriarch of Alexandria, whose latent anti-Constantinopolitan sentiments were immediately aroused. The controversy between the two patriarchs began with a relatively cordial exchange of letters, but soon the words became heated and bitter, with charge answered by countercharge. Nestorius's Antiochene position vis-à-vis the Person of Christ was that "Mary did not give birth to the divinity, but to man, the instrument of divinity." Thus, for him, the two natures of Christ—divine and human—were in intimate harmony, but each functioned according to its own attributes. Cyril, on the other hand, inherited from his Alexandrian tradition the strong emphasis on the essential unity of Christ, so much so that the attributes of one nature could be ascribed to the other. Therefore, theotokos was not just pious; it was a theologically necessary title for the Virgin Mary. In the course of the controversy Nestorius sought and obtained the support of John, the bishop of Antioch, while Cyril astutely won the ear and confidence of Celestine, the bishop of Rome.
The issue was brought to a head at the Council (third ecumenical) of Ephesus, called by Theodosius II in 431. Actually there were two councils, since Cyril and his supporters, without waiting for the delegation from Antioch, met first (June 22) and condemned Nestorius. A week later John of Antioch arrived and, meeting with his supporters, condemned Cyril. On July 10 the Roman envoys arrived, and they joined their voices to the condemnation of Nestorius. Subsequent sessions proved fruitless, so finally imperial pressure was brought to bear. Both patriarchs were declared to be in error, Cyril was imprisoned, and Nestorius was sent back to Antioch. But Cyril's political acumen soon won him freedom and a supposed victory, and, on the orders of the Emperor, Nestorius was exiled to Oasis in Upper Egypt, where some 20 years later he died.
During his exile Nestorius wrote his famous Bazaar of Heraclides, explaining his position in such a way as to lead many scholars to conclude that he was not, as charged, guilty of Nestorianism. The definitive Formula of Chalcedon, promulgated in 451, combined the positions of Cyril and Nestorius in a compromising fashion, with the result that today Christological "orthodoxy" borrows from each. Theological support for Nestorius's views survived his condemnation and exile, expressing itself both in the establishment of Nestorian churches in the East and in the persistent development of his views in the Latin Church.
Further Reading on Nestorius
The most comprehensive and sympathetic monograph on Nestorius is James Franklin Bethune-Baker, Nestorius and His Teaching: A Fresh Examination of the Evidence (1908). A survey of the issues relating to Nestorius's theological position is in George L. Prestige, Fathers and Heretics: Six Studies in Dogmatic Faith with Prologue and Epilogue (1940), and Alois Grillmeier, Christ in Christian Tradition (1965).