Chapter 11 — Part I: The Creed — Article IX: The Holy Catholic Church; the Communion of Saints
Section 51. "I Believe the Holy Catholic Church" — Finally, with regard to the Church, the pastor should teach how to believe the Church can constitute an Article of faith. Although reason and the senses are able to ascertain the existence of the Church, that is, of a society of men on earth devoted and consecrated to Jesus Christ, and although faith does not seem necessary in order to understand a truth which even Jews and Turks do not doubt; nevertheless it is from the light of faith only, not from the deductions of reason, that the mind can grasp those mysteries contained in the Church of God which have been partly made known above and will again be treated under the Sacrament of Holy Orders.