“You must not have sexual relations with your sister, either your father’s daughter or your mother’s daughter, whether she was born in the same home or elsewhere.”
Leviticus 18:9 (BSB)
Context Reading
7You must not expose the nakedness of your father by having sexual relations with your mother. She is your mother; you must not have sexual relations with her. 8You must not have sexual relations with your father’s wife; it would dishonor your father. 9You must not have sexual relations with your sister, either your father’s daughter or your mother’s daughter, whether she was born in the same home or elsewhere. 10You must not have sexual relations with your son’s daughter or your daughter’s daughter, for that would shame your family. 11You must not have sexual relations with the daughter of your father’s wife, born to your father; she is your sister.