,” and the merchant said, “It cost me thirty, and I will sell it only for fifty, payable at a later date.” Is that permissible or not?

He replied:

Buyers fall into three categories:

The first is someone who wants the goods for personal use, whether for eating, drinking, clothing, riding, or other purposes.

The second is someone who intends to trade in them. These two kinds of purchase are permissible according to the Quran, the Sunnah, and scholarly consensus. Allah Most High says:

“Allah has permitted trade.”

And He Most High says:

“Unless it is trade conducted by mutual consent among you.”

However, the conditions prescribed by Islamic law must be observed. If the buyer is compelled by necessity, the goods may only be sold to him at their fair market value. For example, if someone urgently needs to buy food that is available from only one person, that person must sell it to him at its fair market value. If he refuses to sell it for anything less than a higher price, the buyer may take it without his consent, paying its fair market value. If the seller hands it over to him, the buyer owes only its fair market value. If he sells it to him at its fair value with payment deferred until that date, the period of deferment accounts for part of the price.

The third category is someone whose sole purpose in buying is to obtain money—for example, to settle a debt and buy something with it. The two agree that he will give him, for example, one hundred in exchange for one hundred and twenty payable at a later date. All of this is prohibited. If they agree that he will return