ʿAmr ibn al-ʿĀṣ reported that "the Messenger of God—peace and blessings be upon him—ordered him, while collecting the young she-camels due in zakāt, to take one camel in exchange for two until the prescribed amount was reached."

They (the Shāfiʿīs) therefore argue that this establishes both disparity and deferment within a single genus.

The Ḥanafīs, on the other hand, cite the ḥadīth transmitted by al-Ḥasan from Samurah: "The Messenger of God—peace and blessings be upon him—forbade the sale of an animal for an animal." They maintain that this shows sameness of genus by itself is sufficient to bar a deferred transaction.

Mālik bases his prohibition of deferment, where the intended utility of the two animals is identical, on the principle of blocking the means (sadd al-dharīʿah). Such a sale, he says, serves no purpose except to operate as a loan that yields a benefit, which is unlawful. Some have even said he treats it as an independent principle in its own right.

A report from the Kūfan jurists states that selling one animal for another on credit is impermissible whether or not the genus coincides, in line with the literal sense of Samurah’s ḥadīth. Thus al-Shāfiʿī appears to have preferred the report of ʿAmr ibn al-ʿĀṣ, while the Ḥanafīs preferred Samurah’s report—though they interpret it, for its outward wording would outlaw every deferred animal-for-animal sale regardless of genus. Mālik, by contrast, seems to have reconciled the two: he applies Samurah’s ḥadīth to cases where the utilities are the same, and ʿAmr ibn al-ʿĀṣ’s ḥadīth to cases where they differ.

Al-Ḥasan’s having actually heard the ḥadīth from Samurah is disputed, though al-Tirmidhī deemed the chain sound. Supporting Mālik is another report recorded by al-Tirmidhī from Jābir, who related that the Messenger of God—peace and blessings be upon him—said: "Two animals for one may not be sold on credit, but there is no harm in doing so hand-to-hand."

Ibn al-Munḏir further stated that it is firmly established that "the Messenger of God—peace and blessings be upon him—bought a slave for two black slaves and purchased a slave-girl for seven heads." On the strength of this ḥadīth, the sale of one animal for another seems to rest on a textual basis of its own, not merely on the principle of blocking the means.

The jurists also disagreed, concerning goods whose deferred sale is forbidden, whether immediate mutual possession in the same session before the parties separate is required for all other ribā-liable commodities. They all agree that it is mandatory in currency exchange (muṣārafah) because of his statement—peace and blessings be upon him—“Do not sell what is absent among them for what is present.” Those who stipulate possession in the session assimilate these commodities to currency exchange; those who do not contend that taking possession before dispersing is required only where specific evidence demands it. Since the evidence concerns currency exchange alone, the remaining ribā commodities revert to the original rule.