Catechism of the Catholic Church §2673 — excerpt
In prayer the Holy Spirit unites us to the person of the only Son, in his glorified humanity, through which and in which our filial prayer unites us in the Church with the Mother of Jesus.
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.