Feast day: June 27
St. Cyril of Alexandria
Patriarch of Alexandria and the leading theologian of the Council of Ephesus, whose defense of the unity of Christ secured for Mary the title Mother of God ('Theotokos').
Cyril was born about 376 in Egypt and became patriarch of Alexandria, one of the most powerful sees in the Christian world, in 412. A man of forceful character and immense theological learning, he gave his life to defending the unity of the person of Christ — that the one who was born of Mary, who suffered and died, is the very same eternal Son of God, not a man merely joined to God.
The great battle of his life came when Nestorius, the bishop of Constantinople, taught that Mary should be called only the 'Mother of Christ,' not the 'Mother of God' (Theotokos), as though the divine and human in Jesus could be held apart. Cyril saw at once that this threatened the heart of the faith — for if Mary is not the Mother of God, then the child she bore is not truly God — and he led the opposition with all his energy.
At the Council of Ephesus in 431, presiding as the representative of the pope, Cyril secured the condemnation of Nestorius and the solemn definition that Mary is truly Theotokos, the Mother of God, because her Son is one person, both God and man. When the news spread, the people of Ephesus are said to have escorted the bishops home by torchlight in joy.
His writings on the Incarnation became a foundation of Christian belief about Christ for all the centuries that followed, shaping the later councils as well. Honored as a Father and Doctor of the Church, Cyril is remembered as the great defender of the truth that, in Jesus, God himself was born of a woman, suffered, and rose for our salvation.
It was his teaching that carried the day at Ephesus in 431, when the Church defined that Mary is truly the Mother of God.
Source: newadvent.org/cathen/04592b.htm
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