Catechism of the Catholic Church §871 — excerpt
"The Christian faithful are those who, inasmuch as they have been incorporated in Christ through Baptism, have been constituted as the people of God; for this reason, since they have become sharers in Christ's priestly, prophetic, and royal office in their own manner, they are…
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: CIC, Can. 204 para 1 · LG 31
