Leviticus 20:9, 11-12

For every one that curseth his father or his mother shall be surely put to death: he hath cursed his father or his mother; his blood shall be upon him.

And the man that lieth with his father's wife hath uncovered his father's nakedness: both of them shall surely be put to death; their blood shall be upon them. And if a man lie with his daughter in law, both of them shall surely be put to death: they have wrought confusion; their blood shall be upon them.