Catechism of the Catholic Church §935 — excerpt
To proclaim the faith and to plant his reign, Christ sends his apostles and their successors. He gives them a share in his own mission.
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.