(Devarim 22:22) "If there be found (by witnesses) a man lying with a woman cohabited with by a husband": including one who was cohabited with in her father's house": i.e., while betrothed (and not yet married). Variantly: "cohabited with by a husband": R. Yishmael says: Scripture comes to teach us about a yevamah (a woman awaiting levirate marriage) that one who lives with her is not liable (to the death penalty) until he (the yavam) cohabits with her.
"then they shall die": by the unqualified death penalty of the Torah — strangulation.
"also both of them": and not one who performs acts of arousal (without intercourse).
"also both of them": to include those who (might) cohabit with her after them.
"the man who lay with the woman" — though she be a minor;
"and the woman": even though she cohabited with a minor.
"and you shall remove the evil": Remove the doers of evil from Israel.