—may Allah bless him and grant him peace—“When these kinds differ, then sell as you wish, provided the exchange is hand to hand.”

Riba (usury) exists in many forms, some more repugnant than others. The worst and most severe of them is to consume usury that multiplies the debt several-fold. A lender does this when the poor borrower’s payment date arrives and he has no money; the lender says, “I will give you a year’s grace, but I will add to what you owe.” Imagine a man owing 10,000; when he cannot pay, the lender tells him, “I will defer you for a year and make it 11,000.” This is forbidden and impermissible, whether the increase is declared outright or concealed behind a stratagem—such as saying, “Buy this item from me for 11,000 and sell it back to me for 10,000,” so that the borrower ends up liable for 11,000. In this way he schemes against Allah’s sacred limits—Allah’s refuge is sought—and plotting against what Allah has prohibited is uglier than committing the sin openly.

For that reason, those who resort to ruses for usury fall under Allah’s words: “Those who consume usury will not stand except as one whom Satan has confounded with his touch” (Q 2:275).

The scholars have two explanations for this verse. The first is that, because of their greed for usury, they conduct themselves in this world like madmen—rash, reckless, and desperate for unlawful profit. We see those who scheme for usury behaving like lunatics: eager, ravenous, and contriving a new ploy every day.

The second explanation is that they will rise from their graves on the Day of Resurrection like a person seized and convulsed by a jinn—may Allah grant us safety—before the eyes of all witnesses on that awesome Day.