Leviticus 20:14

14 aIf a man takes a woman and her mother also, it is depravity; he and they shall be burned with fire, that there may be no depravity among you.

Deuteronomy 27:23

23 b“‘Cursed be anyone who lies with his mother-in-law.’ And all the people shall say, ‘Amen.’

Amos 2:7

7those who trample the head of the poor cinto the dust of the earth
and dturn aside the way of the afflicted;
ea man and his father go in to the same girl,
so that my holy name is profaned;
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