1. In the previous catechesis, we went over, albeit briefly, the Old Testament testimonies that prepared us to welcome the full revelation, announced by Jesus Christ, of the truth of the mystery of the Fatherhood of God.
Indeed, Christ spoke many times of his Father, presenting his providence and merciful love in various ways.
But his teaching goes further. Let us listen again to the particularly solemn words, recorded by the evangelist Matthew (and paralleled by Luke): 'Bless you, O Father, Lord of heaven and earth, for you have kept these things hidden from the wise and the clever and revealed them to the simple . . ." and later: "Everything has been given to me by my Father, no one knows the Son except the Father, and no one knows the Father except the Son and he to whom the Son wishes to reveal him" (Mt 11:25. 27; cf. Lk 10:2. 11).
So for Jesus, God is not only "the Father of Israel, the Father of men", but "my Father"! "My": for this very reason the Jews wanted to kill Jesus, because "he called God his Father" (Jn 5:18). "His" in the most literal sense: He whom only the Son knows as Father, and by whom alone he is mutually known. We are now on the same ground from which the prologue of John's Gospel will later arise.
2. My Father' is the Father of Jesus Christ, he who is the origin of his being, of his messianic mission, of his teaching. The evangelist John has abundantly reported the messianic teaching that allows us to fathom in depth the mystery of God the Father and Jesus Christ, his only Son.
Jesus says: "Whoever believes in me does not believe in me, but in him who sent me" (John 12: 44). "I did not speak from me, but the Father who sent me, he himself commanded me what I should say and proclaim" (Jn 12:49). "Verily, verily, I say unto you, the Son of himself can do nothing except what he sees the Father do; what he does, the Son also does" (Jn 5:19). "For as the Father has life in himself, so he has granted the Son to have life in himself" (Jn 5:26). And finally: ". . the Father, who has life, has sent me, and I live for the Father" (Jn 6:57).
The Son lives for the Father first of all because he was begotten by him. There is a very close correlation between fatherhood and sonship precisely because of generation: "You are my Son; today I have begotten you" (Heb 1:5). When at Caesarea Philippi Simon Peter confesses: "You are the Christ, the Son of the living God", Jesus answers him: "Blessed are you . . . for neither flesh nor blood has revealed it to you, but my Father . . ." (Mt 16:16-17), for only "the Father knows the Son" just as only the "Son knows the Father" (Mt 11:27). Only the Son makes the Father known: the visible Son makes the invisible Father seen. "He who has seen me has seen the Father" (Jn 14:9).
3. A careful reading of the Gospels shows that Jesus lives and works in constant and fundamental reference to the Father. He often addresses him with the word full of filial love: "Abba"; even during the prayer of Gethsemane this same word returns to his lips (cf. Mk 14:36). When the disciples ask him to teach them to pray, he teaches them the "Our Father" (cf. Mt 6:9-13). After the resurrection, at the moment of leaving the earth he seems to refer once again to this prayer, when he says: "I ascend to my Father and your Father, my God and your God" (Jn 20, 17).
Thus through the Son (cf. Heb 1:2), God revealed Himself in the fullness of the mystery of His fatherhood. Only the Son could reveal this fullness of the mystery, for only "the Son knows the Father" (Mt 11:27). "God no one has ever seen him: it is the only Son, who is in the bosom of the Father, who has revealed him" (Jn 1:18).
4. Who is the Father? In the light of the definitive witness we have received through the Son, Jesus Christ, we have the full knowledge of faith that the Fatherhood of God belongs first of all to the fundamental mystery of God's intimate life, to the Trinitarian mystery. The Father is the one who eternally begets the Word, the Son consubstantial with him. In union with the Son, the Father eternally "breathes forth" the Holy Spirit, who is the love in which the Father and the Son mutually remain united (cf. Jn 14:10).
Thus the Father is in the Trinitarian mystery the "beginning-without-beginning". "The Father by none is made, nor created, nor begotten" (Quicumque symbol). He alone is the beginning of life, which God has in Himself. This life - that is, the very divinity - the Father possesses in absolute communion with the Son and the Holy Spirit, who are consubstantial with him.
Paul, an apostle of the mystery of Christ, falls in adoration and prayer "before the Father from whom all fatherhood in heaven and on earth takes its name" (Eph 3:15), the beginning and model.For there is "one God the Father of all, who is above all, who acts through all and is present in all" (Eph 4:6).
[Pope John Paul II, General Audience 23 October 1985].