dates, this is permissible because the kinds differ. When the kinds differ, equality is not a condition.

Likewise, if dates are sold for wheat without determining the amount, neither by weight nor by volume, this too is permissible, because equality is not required.

In summary: when a ribā commodity is sold for the same kind, two conditions are required:

First: reciprocal possession by both parties.

Second: equality according to the legal standard: goods measured by volume must be exchanged by volume, and goods measured by weight by weight.

When a ribā commodity is sold for another ribā commodity of a different kind, only one condition is required: possession must take place before the parties separate. Equality, however, is not a condition. It is therefore permissible to sell them by volume, by weight, or by estimation.

If they differ in their legal standard—such that one is measured by volume and the other by weight—the jurists say that every arrangement is permissible. That is, sale by volume, by weight, or by estimation is permissible, as are immediate payment and deferred payment. For example, I may sell you one pound of iron for two sāʿs of wheat, payable after one month. This is permissible because iron is measured by weight, whereas wheat is measured by volume.

When a ribā commodity is sold for a non-ribā commodity, the parties may separate before taking possession, and disparity is permissible. For example, one may sell barley for a sheep, or barley for garments, and the like. In such transactions, separation before taking possession and disparity are permissible. This is the summary of what the author, may Allah Most High have mercy on him, has mentioned.

Issue: It is permissible to sell one hundred riyals in paper currency, for example, for five