The nakedness of your son's daughter or your daughter's daughter, their nakedness you shall not uncover; for theirs is your own nakedness.
Leviticus 18:10
Surrounding context
18:9 The nakedness of your sister, the daughter of your father, or the daughter of your mother, whether born at home or elsewhere, their nakedness you shall not uncover.
18:10 The nakedness of your son's daughter or your daughter's daughter, their nakedness you shall not uncover; for theirs is your own nakedness.
18:11 The nakedness of your father's wife's daughter, begotten by your father--she is your sister--you shall not uncover her nakedness.