Leviticus 18:8

18:8 You must not have sexual intercourse with your father’s wife; she is your father’s nakedness.

Leviticus 18:16

18:16 You must not have sexual intercourse with your brother’s wife; she is your brother’s nakedness.

Leviticus 18:20

18:20 You must not have sexual intercourse with the wife of your fellow citizen to become unclean with her.