This is no common occurrence, but a sign; no reason here, but God’s power, for he is the cause, and not nature.
It is a special event, not shared by others; it is divine, not human.
Christ’s birth was not necessity, but an expression of omnipotence, a sacrament of piety for the redemption of men.
[...] Why then, man, are you so worthless in your own eyes and yet so precious to God?
Why render yourself such dishonor when you are honored by him?
Why do you ask how you were created and do not seek to know why you were made?
Was not this entire visible universe made for your dwelling?
It was for you that the light dispelled the overshadowing gloom.
For your sake was the night regulated and the day measured, and for you were the heavens embellished with the varying brilliance of the sun, the moon and the stars.
The earth was adorned with flowers, groves and fruit; and the constant marvellous variety of lovely living things was created in the air, the fields, and the seas for you, lest sad solitude destroy the joy of God’s new creation.
And the Creator still works to devise things that can add to your glory.
He has made you in his image that you might in your person make the invisible Creator present on earth.
He has made you his legate, so that the vast empire of the world might have the Lord’s representative.
Then in his mercy God assumed what he made in you.
He wanted now to be truly manifest in man, just as he had wished to be revealed in man as in an image.
Now he would be in reality what he had submitted to be in symbol.
And so Christ is born that by his birth he might restore our nature.
He became a child, was fed, and grew that he might inaugurate the one perfect age to remain forever as he had created it.
He supports man that man might no longer fall.
And the creature he had formed of earth he now makes heavenly; and what he had endowed with a human soul he now vivifies to become a heavenly spirit.
In this way he fully raised man to God, and left in him neither sin, nor death, nor travail, nor pain, nor anything earthly, with the grace of our Lord Christ Jesus, who lives and reigns with the Father in the unity of the Holy Spirit, now and for ever, for all the ages of eternity.
Peter Chrysologus (c.380 – c.450): Sermon 148, PL 52, 596-598, from the Office of Readings for the memorial of St. Peter Chrysologus on July 30 @ Crossroads Initiative.