Leviticus 20:19–21

19 kYou shall not uncover the nakedness of your mother’s sister or of your father’s sister, for that is to make naked lone’s relative; they shall bear their iniquity. 20 mIf a man lies with his uncle’s wife, he has uncovered his uncle’s nakedness; they shall bear their sin; they shall die childless. 21 nIf a man takes his brother’s wife, it is impurity.2 He has uncovered his brother’s nakedness; they shall be childless.