us.” This was compensation in exchange for setting the captives free, comparable to the consideration under a contract of manumission consisting of a generic obligation to provide camels, due at a [variable], unspecified time.
Al-Bukhārī narrated from Ibn Umar in the hadith of Khaybar that “the Prophet—peace and blessings be upon him—fought them until he forced them to retreat into their fortress and gained control of their land, crops, and date palms. They then reached a settlement with him whereby they would evacuate it, retaining whatever their mounts could carry, while the gold, silver, and arms—that is, the weaponry—would belong to the Messenger of Allah—peace and blessings be upon him—and they would depart from it. He stipulated that they must neither conceal nor hide anything. If they did, they would have neither protection nor covenant.”
This was a settlement involving particular property whose details were unknown. Ibn Abbās said: “The Messenger of Allah—peace and blessings be upon him—concluded a treaty with the people of Najrān for two thousand sets of garments, half to be delivered in Safar and the remainder in Rajab, which they were to deliver to the Muslims; and for the loan of thirty coats of mail, thirty horses, thirty camels, and thirty of every kind of weapon for use in battle. The Muslims would be liable for them until they returned them, should there be a hostile threat or raid in Yemen.” Narrated by Abū Dāwūd.
This was a settlement for garments stipulated only in general terms: their category was known, but they were not described according to the specifications required for a forward sale. Likewise, the horses, camels, and various kinds of arms to be loaned were stipulated only in general terms and left undescribed, contingent upon a condition that might or might not occur.
These texts thus establish that consideration given for something that is not property—as in a dowry, a contract of manumission, the redemption payment in a divorce, a settlement in lieu of retaliation, the jizya, or a peace settlement with belligerents—need not be known with the same precision as a sale price or wage.