Leviticus 18:17

Thou shall not uncover the nakedness of a woman and her
daughter
That is, if a man marries a woman, and she has a daughter, which is the man's daughter-in-law, after the death of his wife he may not marry this daughter; for this daughter is of the same flesh with her mother, who became one flesh with the man she married, and therefore his relation to her daughter is too near to marry her: Jarchi says, if he does not marry the woman, but only deflower her, it is free for him to marry her daughter; but Aben Ezra says, if he has lain with the mother, the daughter is forbidden; however, if he married either of them, the other was forbidden; he could not marry them both, neither in the lifetime of them both, nor after the death of either of them: neither shalt thou take her son's daughter, or her daughter's
daughter, to uncover her nakedness;
not any of her granddaughters, either in the line of her son or daughter; that is, might not lie with either of them, or marry them, and much less then marry her own daughter, these being a further remove from her: [for] they [are] her near kinswomen;
one or other of them, even every one of them, "the rest" and residue "of her" ^F18, of her flesh, who together made one flesh with her; and therefore not to be married to her husband, either in her life, or after her death: it [is] wickedness:
a very great wickedness, abominable in the sight of God, and to be detested by man as vile and impious; it is whoredom, as the Targum of Jonathan renders it.