Leviticus 18:17-19

Common English Bible

¹⁷ You must not have sexual contact with a woman and her daughter. You will not marry her son’s daughter or her daughter’s daughter, thereby uncovering her nakedness. They are her blood relatives; it is shameful. 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.