Wednesday of the Fifteenth week in Ordinary Time
"No one knows the Father except the Son and anyone to whom the Son wishes to reveal him"
It is the Father to whom all existence owes its origin. In Christ and through Christ he is the source of all. In contrast to all else he is self-existent… He is infinite, for nothing contains Him and He contains all things… He is eternally anterior to time, for time is his creation. Let imagination range to what you may suppose is God's utmost limit, and you will find him present there; strain as you will there is always a further horizon towards which to strain... Such is the truth of the mystery of God; such is the expression of the incomprehensible nature of the Father… Let us confess by our silence that words cannot describe him; let sense admit that it is foiled in the attempt to apprehend, and reason in the effort to define.
Yet he has, as we said, in the word 'Father' a name to indicate his nature; he is a Father unconditioned. He does not, as men do, receive the power of paternity from an external source. He is unbegotten,... To the Son only is he known, for “no one knows the Father save the Son and the one to whom the Son wills to reveal him,” and “no one knows the Son except the Father”. Each has perfect and complete knowledge of the Other. Therefore, since “no one knows the Father save the Son”, let our thoughts of the Father be at one with the thoughts of the Son, the only “faithful Witness” (Rv 1,5), who reveals him to us.
It is easier for me to feel this concerning the Father than to say it. I am well aware that no words are adequate to describe his attributes… All this is an acknowledgment of his glory, a hint of our meaning, a sketch of our thoughts, but speech is powerless to tell us what God is, words cannot express the reality… Therefore we may well acknowledge God but we must avoid naming him. Whatever words we use could not express God as he is nor translate his greatness... We must believe in him, must apprehend, must worship; and such acts of devotion must stand in lieu of definition.
Saint Hilary (c.315-367), Bishop of Poitiers, Doctor of the Church
The Trinity 2, 6-7