Roman Catechism 29.18

Chapter 29 — Part III: The Decalogue — The Sixth Commandment

Section 18. Adultery Is Disgraceful — As dread of disgrace strongly stimulates to the performance of duty and deters from the commission of crime, the pastor should also teach that adultery brands its guilty perpetrators with an unusual stigma. He that is an adulterer, says Scripture, for the folly of his heart shall destroy his own soul: he gathereth to himself shame and dishonour, and his reproach shall not be blotted out.