What is the ruling on disposing of funds allocated for the sustenance of army soldiers for purposes other than what they were designated for, such as transferring a portion of the medicine budget to food if there is a surplus, and is it permissible to feed soldiers who are not from the unit, and what is the ruling on the prevailing customs in this regard?

The fundamental principle is the obligation to adhere to the allocations specified by the responsible authority for the disbursement of those funds, unless the official is authorized to deviate from them for the sake of benefit. It is not permissible to contravene what has been commanded, as it constitutes a breach of trust. The payment of remaining provisions for workers or feeding soldiers who are not part of the designated group depends on the permission of the responsible authority, whether it be an explicit text or a prevailing custom. Customary permission is equivalent to actual permission, so if the prevailing custom of work permits it, then there is no harm in it, unless there is a text prohibiting it.