Leviticus 18:18-20

Common English Bible

¹⁸ You must not marry your wife’s sister as a rival and have sexual contact with her while her sister is alive. ¹⁹ You must not approach a woman for sexual contact during her menstrual uncleanness. ²⁰ You must not have sexual relations with the wife of your fellow Israelite, becoming unclean by it.