The next phase of the controversy was brought about due to statements made by Nestorius, Bishop of Constantinople and a representative of the Antiochian school. Nestorius thought of God as merely dwelling in the human Jesus. Cyril wrote to the Bishop of Rome affirming the Nicene Creed and declaring Nestorian views heretical. The Bishop sided with him and enlisted the aid of the emperor, Theodosius II. The emperor called a council to settle the matter.
Impact: This third of the ecumenical councils of the Church met at Ephesus in 431 and condemned Nestorius.