Athanasius on the Incarnation for his Feast Day

For this purpose, then, the incorporeal and incorruptible and immaterial Word of God comes to our realm, howbeit he was not far from us Acts 17:27 before. For no part of Creation is left void of Him: He has filled all things everywhere, remaining present with His own Father. But He comes in condescension to show loving-kindness upon us, and to visit us. And seeing the race of rational creatures in the way to perish, and death reigning over them by corruption; seeing, too, that the threat against transgression gave a firm hold to the corruption which was upon us, and that it was monstrous that before the law was fulfilled it should fall through: seeing, once more, the unseemliness of what was come to pass: that the things whereof He Himself was Artificer were passing away: seeing, further, the exceeding wickedness of men, and how by little and little they had increased it to an intolerable pitch against themselves: and seeing, lastly, how all men were under penalty of death: He took pity on our race, and had mercy on our infirmity, and condescended to our corruption, and, unable to bear that death should have the mastery””lest the creature should perish, and His Father’s handiwork in men be spent for nought””He takes unto Himself a body, and that of no different sort from ours. For He did not simply will to become embodied, or will merely to appear. For if He willed merely to appear, He was able to effect His divine appearance by some other and higher means as well. But He takes a body of our kind, and not merely so, but from a spotless and stainless virgin, knowing not a man, a body clean and in very truth pure from intercourse of men. For being Himself mighty, and Artificer of everything, He prepares the body in the Virgin as a temple unto Himself, and makes it His very own as an instrument, in it manifested, and in it dwelling. And thus taking from our bodies one of like nature, because all were under penalty of the corruption of death He gave it over to death in the stead of all, and offered it to the Father””doing this, moreover, of His loving-kindness, to the end that, firstly, all being held to have died in Him, the law involving the ruin of men might be undone (inasmuch as its power was fully spent in the Lord’s body, and had no longer holding-ground against men, his peers), and that, secondly, whereas men had turned toward corruption, He might turn them again toward incorruption, and quicken them from death by the appropriation of His body and by the grace of the Resurrection, banishing death from them like straw from the fire.

–Athanasius, On the Incarnation of the Word