Chapter 11 — Part I: The Creed — Article IX: The Holy Catholic Church; the Communion of Saints
Section 49. Among these figures the ark of Noah holds a conspicuous place. It was built by the command of God, in order that there might be no doubt that it was a symbol of the Church, which God has so constituted that all who enter therein through Baptism, may be safe from danger of eternal death, while such as are outside the Church, like those who were not in the ark, are overwhelmed by their own crimes.