I understand what your saying but Mary was the mother of the man Jesus not the Mother of God. Since Jesus preExisted before Mary was ever born. So to say she is the mother of God is false.
The Council of Ephesus was held in 431 at the Church of Mary in Ephesus, Asia Minor. The council was called due to the contentious teachings of Nestorius, bishop of Constantinople. St. Cyril, Patriarch of Alexandria, appealed to Pope Celestine, charging Nestorius with heresy. The Pope agreed and gave Cyril his authority to serve a notice to Nestorius to recant his views or else be excommunicated. Before the summons arrived, Nestorius convinced the Emperor Theodosius II, to hold a General council, a platform to argue their opposing views. Approximately 200 bishops were present. The proceedings were conducted in a heated atmosphere of confrontation and recriminations. It is counted as the Third Ecumenical Council, and was chiefly concerned with Nestorianism.Nestorianism emphasized the dual natures of Christ. Patriarch Nestorius tried to answer a question considered unsolved: "How can Jesus Christ, being part man, not be partially a sinner as well, since man is by definition a sinner since the Fall". To solve that he taught that Mary, the mother of Jesus gave birth to the incarnate Christ, not the divine Logos who existed before Mary and indeed before time itself. The Logos occupied the part of the human soul (the part of man that was stained by the Fall). But wouldn't the absence of a human soul make Jesus less human? No, Nestorius answered because the human soul was based on the archetype of the Logos only to become polluted by the Fall, therefore Jesus was "more" human for having the Logos and not "less". Consequently, Mary should be called Christotokos, Greek for the "Christ-Bearer" and not Theotokos, Greek for the "God-Bearer." Cyril argued that Nestorianism split Jesus in half and denied that he was both human and divine. This was essentially a Christological controversy.
At the urging of its president, Cyril of Alexandria, the Council denounced Nestorius' teaching as erroneous and decreed that Jesus was one person, not two separate people: complete God and complete man, with a rational soul and body. The Virgin Mary was to be called Theotokos because she bore and gave birth to God as a man. This council was originally disputed, however, because Cyril started the council prematurely, without all the legates and bishops present. This caused the Eastern bishops, led by John of Antioch, to hold a competing council where they disputed Cyril's council. Over time, Cyril would eventually triumph. This did not resolve the debate over the union of the two natures of Christ, and related issues were debated at the Council of Chalcedon.
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