What is the ruling on money acquired from a transaction that is unlawful according to Sharia, while ignorant of its unlawfulness, then learning of it and ceasing the transaction, whether with the owner's consent or without it? And what is the ruling on money acquired from a transaction about which there is a permissible difference of opinion, where one held the view that it is permissible, whether with the owner's consent or without it? And what is the ruling on dealing with the owners of such money through buying, selling, or gifting if they have no lawful money?

If a person was ignorant of the prohibition of a transaction and earning money with the owner's consent, then their money is permissible (halal (definition)) and they may benefit from it, and they are not required to return it upon repentance. However, if the money was taken without the owner's consent (such as by theft or usurpation), then they are not absolved unless they return it to its owner or donate it on their behalf if it's impossible to reach them or their heirs. And whoever earned money from a transaction whose ruling is disputed, and they believed it to be permissible, then their money is permissible, regardless of whether the payment was made with the payer's consent or without it.