Deuteronomy 22:21-22

21the men of her city must bring the young woman to the door of her father’s house and stone her to death, for she has done a disgraceful thing in Israel by behaving like a prostitute while living in her father’s house. In this way you will purge evil from among you.

22If a man is caught having sexual relations with a married woman both the man who had relations with the woman and the woman herself must die; in this way you will purge evil from Israel.