yet they preach that our visible sun spreads its rays over all manner of offal, but keeps them clean and pure. Therefore, if pure things which are visible can be touched by visible things which are unclean and not share their pollution how much more did the unchangeable and invisible Truth, receiving a soul through the spirit and a body through the soul, take on the whole man without contamination to itself and free him from all infirmities?De agone christiano, c18 n20
What a wonder that two natures infinitely distant should be more intimately united than anything in the world... That the same person should have both a glory and a grief; an infinite joy in the Deity, and an inexpressible sorrow in the humanity; that a God upon a throne should be an infant in a cradle; the thundering Creator be a weeping babe and a suffering man;
It is here, in the thing that happened after the first Christmas, that the profoundest and most unfathomable depths of the Christian revelation lie. 'The Word became flesh' (Jn. 1:14); God became man; the divine Son became a Jew; the Almighty appeared on earth as a helpless human baby, unable to do more than lie and stare and wriggle and make noises, needing to be fed and changed and taught to talk like any other child. ... The more you think about it, the more staggering it gets.Knowing God
By transgressing God's commandment, we became his enemies. Therefore, in the last times, the Lord has restored us to his friendship through his incarnation. He has become the Mediator between God and man, propitiating the Father against whom we have sinned. He has cancelled our disobedience by his obedience and conferred upon us the gift of communion with, and subjection to, our MakerAdversus omnes haereses 5.17.1
the two natures are mutually united without conversion or alteration; the divine nature does not depart from its proper simplicity, nor is the human one either changed into the nature of the divinity or reduced to non-existence, nor is one composite nature made from the two. For a composite nature cannot be homousia (that is, consubstantial) with either of the natures from which it is composedDe fide orthodoxa bk3 c3