One Christ; Man and God by St. Cyril of Alexandria.

Do you see how there Paul calls Him “a man Christ Jesus” “who gave himself for all“, and how here the Apostle calls Him “great God Christ Jesus,” who again “gave himself for us?“. There is here a double proof against them – or rather, for their sake, if they are willing to change their minds. For Paul calls God and Lord the Jesus, whom he has called a man and demonstrates through both of these that he has given himself for us. He says, “a man Christ Jesus, who gave himself as a ransom for us all‘ (1 Tim. 2:5-6). And again: “waiting for the blessed hope, and the manifestation of the glory of our great God and Savior Jesus Christ, who gave himself for us, that he might redeem us from every sin and purify for himself a peculiar people, who are zealous of good deeds” (Titus 2:13 – 14).
If, as they say, Christ Jesus is only a man, who gave himself for us and made us a peculiar people for himself, then we worship a man in the same manner as the pagans and attribute lordly authority to the creation. But this is not the case, God forbid, because we know Christ to be Lord and God. For he, who is God’s Logos, became man for us, partook of human nature and has been born out of ineffable love for humanity with this nature from the holy and unwedded Virgin. But in this, he was God by nature and the Son of God. Therefore, he is called both God and man, and he is the one and the same Christ in each designation.

Cyril of Alexandria,
Against those who are unwilling to confess that the Holy Virgin is Theotokos 13.