Catechism of the Catholic Church §445 — excerpt
After his Resurrection, Jesus' divine sonship becomes manifest in the power of his glorified humanity. He was "designated Son of God in power according to the Spirit of holiness by his Resurrection from the dead".
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.