What is the ruling on the wealth of the owner of a usurious bank, and the ruling on one who works for him in other capacities that assist and strengthen him?

The wealth of an owner of a usurious bank is of two types: the first is permissible (halal), and the second is unlawful (haram), which must be disposed of by spending it on charitable causes if it cannot be returned to its owners. He must also repent. As for dealing with him through buying, selling, gifting, or accepting an invitation, there is no harm in it, just as the Prophet, peace and blessings be upon him, and the Muslims after him, dealt with Jews who were known for usury. However, if the majority of his wealth is unlawful, then one must avoid him, except for buying and selling and similar transactions. Working for him is permissible if the work involves permissible tasks that are separate from unlawful ones. Otherwise, it is not permissible due to the cooperation in sin involved.