Is it permissible to deduct the money that a wife took from her husband without his knowledge for her personal expenses from her deferred mahr, whether in the case of divorce or death, knowing that the deferred mahr is given upon divorce or death and is considered a debt owed by the husband to his wife?

It is permissible for a wife to take money from her husband without his knowledge if he falls short in providing the obligatory maintenance, based on the hadith of Hind bint Utbah. However, if the husband is fulfilling his duty of maintenance, it is not permissible to take from his money without his permission, due to the general texts that prohibit aggression against people's property, such as Allah's saying: "Do not consume your property among yourselves in falsehood." If the wife takes something from her husband's money while he is not negligent, she must return it to him, even secretly. This is not considered part of the deferred mahr (dower) which a woman is not entitled to except upon separation or the expiry of its specified term.