How is the force of the Lord’s prohibition revealed in this verse?
Leviticus 18:7 (ESV)
7You shall not uncover the nakedness of your father, which is the nakedness of your mother; she is your mother, you shall not uncover her nakedness.
The prohibitions in this verse are introduced with the negative lō’ followed by an imperfect verb. This is the strongest form of the negative in the Hebrew. These laws may not be broken.
7 You shall not uncover the nakedness of your father, which is the nakedness of your mother; she is your mother, you shall not uncover her nakedness.