Shepherd of Hermas

"I charge thee, "saith he, "to keep purity, and let not a thought enter into thy heart concerning another's wife, or concerning fornication, or concerning any such like evil deeds; for in so doing thou commitest a great sin. But remember thine own wife always, and thou shalt never go wrong.

For should this desire enter into thine heart, thou wilt go wrong, and should any other as evil as this, thou commitest sin. For this desire in a servant of God is a great sin; and if any man doeth this evil deed, he worketh out death for himself.