They are ordinary men, and as such cannot resist their natural inclinations.

The Catholic Answers

Do you mean that no one with human nature can be pure and chaste? That every young couple entering matrimony can be quite sure that the other has led an evil immoral life up to that moment? If you do not mean that, do you mean that a young man in the world can lead a good life, but suddenly becomes corrupt when he gives himself to a life of closer union with God? Do you think that the devoting of oneself to a life of prayer and to spiritual things makes it much harder to live a good life than it was before? If a man wanted an immoral life he need not become a Priest in order to attain his desire; nor would he dream of taking a solemn vow of chastity for the sheer joy of making himself doubly guilty in breaking it. And do you, a Protestant, include in your indictment all unmarried Protestant ministers and celibate clergymen?

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty