[Ruling on a Woman Retracting What She Had Remitted of the Dowry]

Answer—and Allah grants success: As a general rule, a wife’s soul rarely feels truly content to part with something in favor of her husband. If she gave him, for example, her gold and waived her claim, it was only to maintain his affection and good companionship. Therefore, if she waived and permitted him to dispose of it, then he divorced her and she came demanding it, the husband is obliged to return what he took from her.
This is indicated by His saying: “But if they, of their own good pleasure, remit to you anything of it, then consume it in satisfaction and ease.” [an-Nisāʾ:4]. The indication here is that the conditional particle “if” conveys, as rhetoricians note, the rarity of the condition’s occurrence; and the wording “they, of their own good pleasure, remit to you anything of it” makes lawful consumption contingent upon that inner contentment—suggesting that when a wife demands from her husband what she had given, she is not content.
Moreover, His saying “anything of it” suggests that a wife is unlikely to remit to her husband all of her dowry or all of her gold.
If it is said: Contentment is an inward matter known only to the wife. If she expresses what indicates it—such as a gift, waiver, or release or something similar indicating satisfaction and acceptance—then it should be acted upon for the lawfulness of consuming it; otherwise, none of a wife’s dowry would ever be lawful to consume.
We reply: What you mentioned is the apparent rule and may be acted upon—so long as nothing appears from her that contradicts it.
Source: Min Thimār al-ʿIlm wa al-Ḥikmah vol.1