Catechism of the Catholic Church §523 — excerpt
St. John the Baptist is the Lord's immediate precursor or forerunner, sent to prepare his way. "Prophet of the Most High", John surpasses all the prophets, of whom he is the last.
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.
Whole chapters cited: John 1