How the Council of Ephesus Acted Decisively and Tragically to Condemn the Church of the East.
Nestorius (386-451) was a careful student of the Bible. As a teenager he entered a monastery located at what is today the Turkish city of Maraş. There Nestorius became a student of Theodore of Mopsuestia (350-428), the most well-known teacher of the Church of the East. Theodore held to the literal sense of Scripture; that is, he did not make up allegories, so popular in Alexandria, which interpreted every Bible text by two or three levels of meaning.
In 428 Nestorius was appointed patriarch of Constantinople (There were five patriarchs; the others resided in Alexandria, Rome, Jerusalem and Antioch). But a doctrinal dispute flared up over the proper title for Mary. Nestorius wrote that she should be called the Mother of Christ. This brought him into conflict with Cyril, the patriarch of Alexandria, who held that Mary should be called the Mother of God. Cyril accused Nestorius of denying the deity of Christ. That was not true, but an uproar against Nestorius followed. Nestorius asked the Emperor to convene a council that would resolve this doctrinal issue. A council convened in Ephesus in 431 to determine a judgment in the manner. Unbelievable things happened there. Samuel Moffett wrote:
Ephesus, 431, was the most violent and least equitable of all the great councils. It was an embarrassment and blot on the history of the church. Cyril opened the proceedings before the patriarch of Antioch, who favored Nestorius on this issue, could arrive. The meeting thus opened with one of the five patriarchs missing. Nestorius refused to attend, and later wrote his own version of what happened:
They acted as if it was a war they were conducting, and the followers of the Egyptian (Cyril) went about the city armed with clubs . . . with the yells of barbarians, snorting fiercely . . . lying about, drunk, shouting obscenities. . . . 
So tense was the situation that a guard surrounded the house in which Nestorius lodged to prevent his murder. At Cyril’s bidding the council proceeded to vote two hundred to nil to excommunicate Nestorius. John, Patriarch of Antioch, with forty bishops, arrived too late to do anything but declare the result illegal and hold a counter council to excommunicate Cyril. Confronted by an impasse that threatened to tear his Byzantine empire apart, Theodosius II reluctantly decided to accept the deposition of both patriarchs. However, Cyril promptly bribed his way back to power. Nestorius, on the other hand, after protesting the injustice, obediently went into exile first to his old monastery near Antioch and then, in 435, on to Petra in Arabia. Nestorius then moved far into the Egyptian desert, where he died in about 451—to the western church a heretic, to the Persian church a hero and a martyr. But to himself, neither heretic nor hero. Near the end of his life Nestorius wrote:
Earthly things have little interest for me. I have died to the world and live for Him. As for Nestorius, let him be anathema! And would God that all men by anathematizing me might attain to reconciliation with God . . . . Farewell desert, my friend . . . and [farewell] exile, my mother, who after my death shall keep my body until the resurrection. Amen.
“Nestorianism” Examined. Nestorius’ writings were burned; only fragments survive. Luther, after looking over all he could find of his writings, decided there was nothing heretical about them. Then, dramatically, in 1889 a Syrian priest discovered an eight-hundred-year-old Syriac manuscript written about 540, recording Nestorius’ own account, in Greek, of his controversies and teachings. This much became clear: Nestorius was not at ease with technical and semantic theological distinctions. But he was convinced that his doctrine was was biblically orthodox. At no time did he deny the deity of Christ, as was charged against him.
At the Council Chalcedon, convened the year Nestorius died in 451, the church leaders declared, or conceded, that “Christ has two natures.” This was precisely what Nestorius stood for and what Cyril of Alexandria denied. Now it was the Alexandrians’ turn to be branded with the stigma of a heresy of their own, Miaphysitism (or Monophysitism). [From that time the Egyptian Church established a separate, national identity, the National Coptic Church]
As for the doctrinal problem of the relationship between Jesus Christ’s two natures, not even the Chalcedon Council was able to define it; the Council could only confess it, and affirm the two natures are preserved “without confusion, without change without division, without separation.”
Conclusion. To some, Nestorians are heretics, condemned by ecumenical councils more than 1500 years ago. To others they are ancient and apostolic Asian Christians untainted by the perversions of Western Greek philosophy. And, of course, many have forgotten the Nestorians altogether. Moffett:
The general consensus of scholarship today would probably agree with A. R. Vine’s observation that Nestorius was the better man but Cyril the better theologian. Chalcedon was probably right in recognizing that Nestorius’ phrase prosopic union” was not strong enough to bear the strain of maintaining the essential unity of the person of Christ. The West, at least, was satisfied with Chalcedon, but not so Egypt, and, to a lesser extent, Persia.
A sorrowful rending of the church had taken effect. The Church in Roman broke off contact with the Church of the East, which for the next thousand years as the Nestorian Church.
 Ibid. 172
 Ibid. 174
 Ibid. 175
 Ibid. 180
 Ibid. xiv
 Ibid. 180