EPHESUS, COUNCILS OF. Two church councils at Ephesus have acquired historic importance.
(a) In June 431 a council was convened here to deal with the Nestorian doctrine of the person of Christ. The councils of Nicea and Constantinople had asserted the full divinity and real humanity of Christ, without, however, defining the manner of their union. The attempt to solve the apparent incongruity of a perfect union of two complete and distinct natures in one person pro duced first Apollinarianism, which substituted the divine Logos for the human vows or caveuµa of Jesus, thereby detracting from the completeness of his humanity; and then Nestorianism, which destroyed the unity of Christ's person by affirming that the divine Logos dwelt in the man Jesus as in a temple, and that the union of the two was in respect of dignity, and furthermore that, inasmuch as the Logos could not have been born, to call Mary "Godbearer," was absurd and blasphemous. The Alex andrians, led by Cyril, stood for the "monophysite" doctrine of the perfect union of two complete natures in one person, and made OEOTOKOS the shibboleth of orthodoxy. The theological controversy was intensified by the rivalry of the two patriarchates, Alexandria and Constantinople, for the primacy of the East. As bishop of Constantinople Nestorius naturally looked to the emperor for support, while Cyril turned to Rome : but the Ephesian council of 431 condemned his doctrine and declared him excommunicate, and deposed. Cyril apparently regarded this as a declaration of the mind of the church in favour of the "monophysite" Chris tology.
(b) The so-called "Robber Synod" of Ephesus was held in 449. Eutyches, who held a form of the "monophysite" doctrine, had been deposed by his bishop, Flavianus of Constantinople, and had appealed to Dioscurus, successor of Cyril in the see of Alexandria, who restored him and moved the emperor Theodosius II. to summon a council which should "utterly destroy Nestorian ism." The council, which was convened in August, 449, was entirely dominated by Dioscurus. Eutyches was acquitted of heresy and reinstated, Flavianus and other bishops deposed, the Roman legates insulted, and all opposition overborne by intimida tion or actual violence. Leo I. of Rome refused to recognize the council, excommunicated Dioscurus, and demanded a new and greater council. The death of Theodosius II. removed the main support of Dioscurus, and cleared the way for the council of Chalcedon (q.v.), which deposed the Alexandrian and condemned Eutychianism.
See MONOPHYSITES, NESTORIANS and references there given, and the general histories of Dogma (especially Harnack and Loofs) and the general Church Histories on the Christological controversies of the 5th century.