The Word of God Himself,
Who is before all worlds, the Invisible, the Incomprehensible, the Bodiless, the Beginning of beginning, the Light of Light, the Source of Life and Immortality, the Image of the Archetype, the Immovable Seal, the Unchangeable Image, the Father’s Definition and Word,
came to His Own Image, and took on Him Flesh for the sake of our flesh, and mingled Himself with an intelligent soul for my soul’s sake, purifying like by like; and in all points except sin was made Man….
He came forth, then, as God, with That which He had assumed; one Person in two natures….O new commingling; O strange conjunction! The Self-existent comes into Being, the Uncreated is created, That which cannot be contained is contained by the intervention of an intellectual soul mediating between the Deity and the corporeity of the flesh. And He who gives riches becomes poor; for He assumes the poverty of my flesh, that I may assume the richness of His Godhead. He that is full empties Himself; for He empties Himself of His Glory for a short while, that I may have a share in His Fullness.
-Gregory of Nazianzus (325-389)