Is taking money from the husband without his knowledge considered forbidden, and how can one atone for this sin after divorce?

If the husband does not provide sufficient maintenance (nafaqa) and clothing (kiswa) according to what is customary (bil-ma'ruf), then it is permissible for the wife to take from his money without his knowledge what suffices her and her children, in a customary manner, just as the Prophet permitted it for the wife of Abu Sufyan. However, if he does spend according to what is customary, then what is taken from his money without his knowledge is considered treachery and must be returned. Accusing the wife of being a sorceress is not permissible except with clear proof.