Council of Ephesus Ephesus: One of the Seven Churches of the Book of Revelation Church of Mary, Ephesus: This is the exact spot now in ruins where the Council of Ephesus was convened. The Council of Ephesus was a pivotal moment in Christian history. It went down in 431 CE, in Ephesus, modern-day Turkey. The council was convened by Emperor Theodosius II to settle some major theological disputes, particularly about the nature of Jesus Christ and the Virgin Mary. The main issue was Nestorianism, a