Leviticus 20:20-24

If there is a man who sleeps with his uncle’s wife, he has uncovered his uncle’s nakedness; they will bear their sin. They will die childless.

If there is a man who takes his brother’s wife, it is detestable; he has uncovered his brother’s nakedness. They will be childless.

‘You are therefore to keep all My statutes and all My ordinances, and do them, so that the land to which I am bringing you to live will not vomit you out.

Furthermore, you shall not follow the customs of the nation which I am going to drive out before you, because they did all these things; therefore I have felt disgust for them.

So I have said to you, “You are to take possession of their land, and I Myself will give it to you to possess, a land flowing with milk and honey.” I am the Lord your God, who has singled you out from the peoples.