Because of its indefectibility the truths revealed by God will always be taught in the Catholic Church. Saint Ambrose said: “The Church is like the moon; it may wane, but never be destroyed; it may be darkened, but it can never disappear.” Saint Anselm said that the bark of the Church may be swept by the waves, but it can never sink, because Christ is there. When the Church is in greatest need, Christ comes to its help by miracles, or by raising up saintly men to strengthen and purify it. It is the bark of Peter; when the storm threatens to sink it, the Lord awakens from His sleep, and commands the winds and waters into calm: “Peace; be still!”
—My Catholic Faith (book)
https://angeluspress.org/products/my-catholic-faith
