Nestorius (/ˌnɛsˈtɔriəs/; in Greek: Νεστόριος; c. 386 – 450) was Archbishop of Constantinople from 10 April 428 until August 431, when the emperor Theodosius II confirmed his condemnation by the Council of Ephesus on 22 June.His teachings included a rejection of the long-used title of Theotokos, "Mother of God", for Mary, mother of Jesus, and were misunderstood by many to imply that he did not believe that Christ was truly God.