"This is my beloved Son, with whom I am well pleased."
Believe in Jesus Christ, Son of the living God but, according to the Gospel, God’s only son: “God so loved the world that he gave his only son, so that everyone who believes in him might not perish but might have eternal life,” (Jn 3:16)…
He is Son of God by nature not by adoption, for he was born of the Father… For the Father, being true God, begot the Son in his own likeness as true God… Christ is son according to nature, a true son not an adopted son as you, the newly baptised, are in becoming children of God. For you, too, become sons but by adoption, according to grace, as it is written: “To those who did accept him he gave power to become children of God, to those who believe in his name…” (Jn 1:12). As for us, we have been born of water and the spirit (Jn 3:5) but not in the same way as Christ was begotten of the Father. Because, while he was being baptised, the Father spoke out and said: “This is my Son.” He did not say: “This man has now become my Son” but: “This is my Son” so as to show that he was Son even before the moment of baptism.
The Father begot the Son in a different manner than the one in which, in our case, the spirit brings forth words. Because the spirit within us subsists, while our words, once they have been spoken and emitted, are dispersed. But we know that Christ has been begotten as Word: not as speech uttered but as subsistent and living, not as spoken and issuing from the lips but as born eternally from the Father in a substantial and ineffable way. For “In the beginning was the Word – God’s speech – and the Word was with God, and the Word was God,” (Jn 1:1), sitting at his right hand (Ps 110 [109]:1). He is that Word who knows the Father’s will and carries out all things at his command, the Word who descends and ascends (Eph 4:10)…, the Word who speaks and says: “I tell you what I have seen in the Father’s presence,” (Jn 8:38), a Word full of authority (cf Mk 1:27) who rules over all, for “the Father has given everything over to the Son,” (Jn 3:35).