If a debtor is obligated to pay dinars and authorizes the creditor to sell his house and take his due right from the proceeds, which are in dirhams, is the creditor allowed to take the dirhams to settle the dinar debt?
Chapter on Riba (Usury) and Exchange (Sarf)
Al-Mughni
Book of Sales
Primary text
The creditor is not permitted to take the dirhams to settle the dinar debt because the debtor has not authorized the creditor to act as his own agent in performing the currency exchange (Sarf). Furthermore, the creditor is suspected of self-interest in such an arrangement.