EUSEBIO of DORILEO. — A zealous and learned layman, highly prominent in Constantinople, he later became bishop of Dorileo. He publicly opposed Nestorius during the sermon delivered at Christmas 428, and posted a public accusation against him, in which he denounced him as guilty of the same heresy as Paul of Samosata. After Nestorius had been condemned, he, by then bishop of Dorileo and a friend of Eutyches, did not hesitate to present to Flavian, bishop of Constantinople, on 8 November 448, a formal accusation against the heresy of Eutyches.
During the “Robber Council of Ephesus,” Dioscorus secured a prohibition against E. appearing, despite the protests of Flavian and the papal legates. Eutyches was rehabilitated, while Flavian and E. were condemned, deposed, and imprisoned. After having a personal appeal delivered to the Pope by two of his clerics, E. managed to escape and took refuge in Rome, where he was still present in April 451 (letter of St Leo the Great to Pulcheria, Epist., LXXIX, 3: PL 54, 912). When the Council of Chalcedon opened, he sent Emperor Marcian and the Council a petition, in which he sought justice for himself against Flavian and accused Dioscorus of heresy. The rehabilitation of E. and the condemnation of Dioscorus inevitably followed. E., however, took part in the approval of canon 28, which established for the Church of Constantinople the primacy of honour, after Rome, despite the refusal of the papal legates. The date of his death is unknown.