The Third Ecumenical Church Council of Ephesus (AD 431)

The third Ecumenical Church Council was convened by emperor Theodosius II in 431. Approximately 150 bishops, primarily from the Greek eastern church, met together in Ephesus’ Church of Mary from June 22 to July 31. Roman Catholic Pope Celestine did not attend, but sent representatives. The purpose of the council was to examine the teaching of Nestorius. Bishop Cyril of Alexandria quickly led the Council to condemn Nestorius’ teaching and supported honoring the Virgin Mary with the title Theotokos, the Mother of God.