How can the Godhead be in the flesh? In the same way as fire can be in iron: not by moving from place to place but by the one imparting to the other its own properties. Fire does not speed towards iron, but without itself undergoing any change it causes the iron to share in its own natural attributes. The fire is not diminished, and yet it completely fills whatever shares in its nature. So is it also with God the Word. He did not relinquish his own nature, and yet “he dwelt among us.” He did not undergo any change, and yet “the Word became flesh.” Earth received him from heaven, yet heaven was not deserted by him who holds the universe in being….
Let us strive to comprehend the mystery. The reason God is in the flesh is to kill the death that lurks there. As diseases are cured by medicines assimilated by the body, and as darkness in a house is dispelled by the coming of light, so death, which held sway over human nature, is done away with by the coming of God. And as ice formed on water covers its surface as long as night and darkness last but melts under the warmth of the sun, so death reigned until the coming of Christ; but when the grace of God our Savior appeared and the Sun of justice rose, death was swallowed up in victory, unable to bear the presence of true life. How great is God’s goodness, how deep his love for us!
Basil the Great, Homily on Christ’s Ancestry, 2.6, quoted in Joel C. Elowsky (ed), John 1-10, Ancient Christian Commentary on Scripture New Testament IVa (InterVarsity Press, 2006) 42.