Catechism of the Catholic Church §1223 — excerpt
All the Old Covenant prefigurations find their fulfillment in Christ Jesus. He begins his public life after having himself baptized by St. John the Baptist in the Jordan.
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.