Leviticus 20:10-12

10And a man that committeth adultery with a man's wife, who committeth adultery with his neighbour's wife, — the adulterer and the adulteress shall certainly be put to death.

11And a man that lieth with his father's wife hath uncovered his father's nakedness: both of them shall certainly be put to death; their blood is upon them.

12And if a man lie with his daughter-in-law, both of them shall certainly be put to death: they have wrought confusion; their blood is upon them.