Nestorius was a monk from Antioch when, in 428, Emperor Theodosius II appointed him to be Patriarch of Constantinople, arguably the most powerful position in the Christian Chu…rch. He was not a great theologian but someone pedantically anxious to put across the Antiochene line in Christology which stressed the full reality of Jesus's humanity. Hence he objected to the title Theotokos , "Mother of God", as applied to Mary, because it seemed to imply that she was Christ's mother according to his godhead, not his manhood. While some could only allow her to be called Anthropotokos , "mother of the man", Nestorius insisted that the right word must be Christotokos , "mother of Christ". The followers of Nestorius, the Nestorians, were excluded by the Orthodox Church in 431. On such flimsy and apparently inconsequential grounds are 'heresy' and schism built. ( Full Answer )

Nestorius has written: 'Nestoriana' -- subject(s): Christian Heresies, History, Nestorians 'Nestoriana' -- subject(s): Accessible book