Today we Christians celebrate a threefold birth which should make all our hearts overflow with joy, in praising and loving God. We should be beside ourselves with gratitude and gladness. If we do not feel this there must be something wrong with us.
The first and most sublime of these three births which we celebrate today is the birth, within the Godhead, of the only Son of the Heavenly Father, divinely begotten by Him and distinct from Him in person only. The second is His human birth, when Mary became His mother without any loss of her virgin purity. The third is the spiritual birth; every day and at every hour God is born into the souls of all just men, through grace and love…
The Father eternally begets His Son. God's nature is so superabundantly, so transcendentally rich that He could not contain or restrain Himself. He had to pour Himself out and give Himself. Boethius and St Augustine say that it is God's nature and character to pour Himself out, and so the Father poured Himself out in the procession of the divine Persons and then He poured Himself out to His creatures. This is why St Augustine said: "We exist only because God is good. Whatever goodness His creatures have, they owe it all to the essential goodness of God."
God first turns in and knows Himself, then goes out from Himself in begetting His Image (which is His own knowledge and understanding of Himself) and then returns again to Himself in perfect delight in His own being. And this delight flows out in an ineffable love which is the Holy Ghost; and so God remains with Himself, goes out from Himself and returns again to Himself. . . .
Now our soul is a true image of the Holy Trinity. It has three noble faculties: memory, understanding and free will. Through these faculties the soul is capable of grasping and receiving God; it can receive everything that God is and has and can give; and so it can look into eternity, because it has been created between time and eternity. By its higher faculties the soul is in touch with eternity; by its lower faculties, which are sensible and animal, it is in touch with time. But because these higher and lower faculties are interrelated, the soul applies them both to temporal things and so it is hampered in its course and is always apt to turn toward time and away from eternity.