Unfortunately in this secular age often Muslims do not seek to learn the Shariah rules properly before engaging in actions thus fall into sin for not learning the rule before acting and secondly run the risk of falling into the kaba'ir sins like riba . The following chapter from the excellent work, 'The Economic System in Islam' by Sheikh Taqiuddin an-Nabhani elaborates the Islamic rules of currency exchange. Riba and Currency Exchange ( Sarf ) riba (interest/usury) is the practice of taking property (or anything that serves as a medium of exchange) for another property of the same type unequally. The money exchange ( Sarf ) is the practice of taking a property for another property from gold and silver of the same type equally, or of two different types equally or unequally. The exchange can only take place in trade, as for usury, it can only happen in a trade ( bay’u ) transaction, in a loan ( qardh ) or in a Salam (advance sale or forward buying). Trading...
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