Chapter 29 — Part III: The Decalogue — The Sixth Commandment
Section 12. First of all they should be taught that although the virtue of chastity shines with a brighter lustre in those who make the holy and religious vow of virginity, nevertheless it is a virtue which belongs also to those who lead a life of celibacy; or who, in the married state, preserve themselves pure and undefiled from unlawful desire.