Leviticus 18:6-9

⁶None of you shall approach to any that is near of kin to him, to uncover their nakedness: I am the Lord.

⁷The nakedness of thy father, or the nakedness of thy mother, shalt thou not uncover: she is thy mother; thou shalt not uncover her nakedness.

⁸The nakedness of thy father’s wife shalt thou not uncover: it is thy father’s nakedness.

⁹The nakedness of thy sister, the daughter of thy father, or daughter of thy mother, whether she be born at home, or born abroad, even their nakedness thou shalt not uncover.