Deuteronomy 22:21-22

21then they shall bring her out to the doorway of her father’s house, and the men of her city shall stone her to death because she has committed a deliberate sin in Israel by playing the prostitute in her father’s house. So you shall remove the evil from among you.

22“If a man is intimate with a woman who is another man’s wife, they shall both be put to death, the man who lay with the woman, and the woman. So you shall remove the evil from Israel.