TSK · Leviticus 20:10

"'You shall not lie carnally with your neighbor's wife, and defile yourself with her.

If a man be found lying with a woman married to a husband, then they shall both of them die, the man who lay with the woman, and the woman: so you shall put away the evil from Israel.

David said to Nathan, "I have sinned against Yahweh." Nathan said to David, "Yahweh also has put away your sin. You will not die.

For that would be a heinous crime. Yes, it would be an iniquity to be punished by the judges:

they told him, "Teacher, we found this woman in adultery, in the very act.