In the mystery of our Lord’s incarnation there were clear indications of his eternal Godhead. Yet the great events we celebrate today disclose and reveal in different ways the fact that God himself took a human body. Mortal man, enshrouded always in darkness, must not be left in ignorance, and so be deprived of what he can understand and retain only by grace. In choosing to be born for us, God chose to be known by us. He therefore reveals himself in this way, in order that this great sacrament of his love may not be an occasion for us of great misunderstanding.
From a sermon by Saint Peter Chrysologus, bishop