Dr. Monzer Kahf, a prominent economist and counselor states: The Prophet, peace and blessings be upon him, himself determined the conditions of currency trading. In a saying that is highly regarded, reported by both Bukhari and Muslim, he put the condition that currency trading must be “Yadan bi Yad. This means that currency trading must be done only spot (immediate debit and credit of both currencies) and with full payment of both currencies too. By these two conditions we are actually excluding two kinds of transactions, and may be others too): margin trading and future trading.