“Abu ‘Abd Allah (a.s.), has said that once a man came to my father and said, ‘I have inherited a certain amount of property and I knew the owner from whom I inherited received Raba’ and I know with certainty there is Riba’ in it and I do not feel happy to consume it because of my knowledge about it. I asked the scholars of law of Iraq about it and they said, ‘It is not lawful to consume it.’ Abu Ja‘far (a.s.), said, ‘If you know exactly Riba’ property in it and you know the owner also, you must separate it and return to the owner. If it is mixed you can consume it in good health and pleasure. It is your property but you must stay away from what the previous owner would do. The Messenger of Allah, O Allah, grant compensation to Muhammad and his family worthy of their services to Your cause, granted relief to what is passed and prohibited from Riba ’ in coming times. If one is ignorant he is exempt, until he comes to know of the unlawfulness of Riba Once a person learns that Riba ’ is unlawful and punishment becomes necessary if one consumes Riba’ just as it (punishment) is necessary for one who has consumed Riba’.’”