Leviticus 18:7-8

18:7 You must not ¹  expose your father’s nakedness by having sexual intercourse with your mother. ²  She is your mother; you must not have intercourse with her. 18:8 You must not have sexual intercourse with your father’s wife; she is your father’s nakedness. ³ 

[18:7]  ¹ tn The verbal negative here is the same as that used in the Ten Commandments (Exod 20:4-5, 7, 13-17). It suggests permanent prohibition rather than a simple negative command and could, therefore, be rendered “must not” here and throughout the following section as it is in vv. 3-4 above.

[18:7]  ² tn Heb “The nakedness of your father and [i.e., even] the nakedness of your mother you shall not uncover.”

[18:8]  ³ tn Heb “the nakedness of your father she is.” See the note on v. 7 above. This law refers to another wife of the man’s father, who is not that man’s mother. The laws in the Pentateuch sometimes assume the possibility that a man may have more than one wife (cf., e.g., Deut 21:15-17).