Read Leviticus 19:20 Using Other Translations
And whosoever lieth carnally with a woman, that is a bondmaid, betrothed to an husband, and not at all redeemed, nor freedom given her; she shall be scourged; they shall not be put to death, because she was not free.
"If a man lies sexually with a woman who is a slave, assigned to another man and not yet ransomed or given her freedom, a distinction shall be made. They shall not be put to death, because she was not free;
“If a man has sex with a slave girl whose freedom has never been purchased but who is committed to become another man’s wife, he must pay full compensation to her master. But since she is not a free woman, neither the man nor the woman will be put to death.