If someone asks: What is the basis for describing it as evil and falsehood?

We say: This formula—“You are to me like my mother’s back”—contains both a statement and a legal declaration. The statement is that his wife is like his mother’s back, and this is falsehood and a lie. The declaration is the pronouncement that she is unlawful to him, and this is prohibited; hence, it is evil. Thus, it is evil insofar as it constitutes a declaration of ẓihār, and falsehood insofar as it is a lie.

As for its definition, the author states:

“Whoever likens his wife, or any part of her, to any part or the whole of a woman whom he is permanently forbidden to marry because of blood relationship or breastfeeding, whether it be her back or her belly.”

His words, “Whoever likens,” are general and include both an adult and a minor. They do not include an insane person, however, because an insane person has no intention. Thus, ẓihār pronounced by a minor husband is valid.

It is understood from his words, “his wife,” that he must have contracted a valid marriage with her. If he pronounces ẓihār concerning a woman and then marries her afterward, it does not constitute ẓihār, because she was not his wife when he pronounced it. This is what the author’s words indicate, and it is correct: ẓihār is valid only in relation to one’s wife.

The well-known position in the madhhab is that ẓihār pronounced concerning an unrelated woman whom he has not married is valid. Thus, if he says to a woman whom he has not married, “You are to me like my mother’s back,” then marries her, they say: He must not have intercourse with her or approach her until he offers the expiation for ẓihār. The correct view is that it is not valid. The evidence is Allah’s saying, Most High: “Those who pronounce ẓihār of their wives” [al-Mujādilah 58:3]. A woman is not among their wives except through a marriage contract. This is analogous to His saying: “For those who swear abstinence from their wives” [al-Baqarah 2:226].

His words, “or any part of her,” mean that he likens a part of her. For example, if he says, “Your hand is to me like my mother’s back,” we say: This is ẓihār, because prohibition cannot be divided; thus—