"You shall not commit adultery" is one of the Ten Commandments. Adultery is sexual relations in which at least one participant is married to someone else. According to the Genesis narrative, marriage is a union established by God himself. For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh. – Genesis 2:24 (NIV) – Proverbs 6:32-35 (JPS) Adultery is one of three sins (along with idolatry and murder) the Mishnah says must be resisted to the point of death. – Hebrews 13:4 (NIV)