Catechism of the Catholic Church §950 — excerpt
Communion of the sacraments. "The fruit of all the sacraments belongs to all the faithful. All the sacraments are sacred links uniting the faithful with one another and binding them to Jesus Christ, and above all Baptism, the gate by which we enter into the Church.
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.
Also cites: Roman Catechism 1, 10, 24