But the Gospel, the “good news” of Jesus of Nazareth passed on from generation to generation in the community of believers, tells us not only that God exists and that he is one: it also — and especially — tells us who he is. In the Spirit the Son leads his disciples to a loving knowledge of the Father and to the Trinitarian communion. In baptism, in fact, the Christian is immersed into the death and resurrection of Christ, receives the Holy Spirit, and is proclaimed “son” of the Father; he thus becomes a member of Christ’s body, which is the Church: ecclesiology is intimately connected with the mysteries that are at the heart of Christian revelation. The Tri-unity of God can be known only through the plural unity of the catholic Church — that is, literally, the Church “aggregated according to the whole” — and, equally, the Church possesses its “catholicity” only because the Son and the Spirit, sent by the Father, have unveiled to it the Trinity, not as an abstract intellectual fact, but rather as rule, norm, canon of its own life.