Leviticus 18:18-20

Amplified Bible

¹⁸ You shall not marry a woman in addition to her sister as a rival while she is alive, to uncover her nakedness.

¹⁹ ‘Also you shall not approach a woman to uncover her nakedness during her menstrual impurity and ceremonial uncleanness. ²⁰ You shall not have intimate relations with your neighbor’s wife, to be defiled with her.