All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If your husband is unable to rightly manage his money such that he can be labeled as foolish in his money-related behavior, even if he is religious, then you are allowed to submit his case to the Sharee'ah court that may place him under guardianship. You are allowed neither to issue such a verdict upon him nor to place him under guardianship of your own accord, even after the judgment has been passed against him.
You should know that such matters, spendthrift, extravagance and foolishness, are relative, depending on a person'sown viewpoint. So we need a definite authority to put a criteria for this; and this is exclusive nowadays to adjudication.
You can resort to other means than taking his money without informing him, namely, offering him advice and asking his relatives and companions to advise him. The advice should, however, be given in a wise manner that entails softness and speaking leniently with no rigorousness, harshness or severity as this would lead to nothing but stubbornness. Allaah The Almighty Says (what means):
· {And give the relative his right, and [also] the poor and the traveler, and do not spend wastefully. Indeed, the wasteful are brothers of the devils, and ever has Satan been to his Lord ungrateful.} [Quran17: 26-27]
· {Verily, He likes not the extravagant.} [Quran 6:141]
You can also remind him of the status of poverty, indigence and lack of provision that the Prophet, sallallaahu ‘alayhi wa sallam, and his Companions underwent, and of the poverty and need that many Muslims are suffering. All this will be fruitful and will change his conduct, in shaa’ Allaah (if Allaah wills).
First and foremost though, you ought to supplicate to Allaah The Almighty to guide him and make him an upright person.
Allaah Knows best.