Is it permissible to take money from a brother who borrowed it from an interest-based bank when he is not in need of it, and what should be done with it if it is permissible to take it?

The aforementioned money must be taken without the usurious interest and returned to its owners if possible, without a greater harm; this is for changing the evil and advising the brother, in accordance with the Prophet's (peace and blessings be upon him) saying: "Help your brother, whether he is an oppressor or oppressed." If that is not possible, then only advising the brother is obligatory. It is not permissible to take his money without his permission, because a Muslim's money is sacred, as the Prophet (peace and blessings be upon him) said: "Every Muslim's blood, wealth, and honor are sacred to another Muslim."