It is nevertheless permissible to burn a lamp with ritually impure oil provided that this is done outside a mosque. The sale of a Qur’an codex is forbidden, and such a sale is invalid if the purchaser is a non-Muslim.

Another condition is that the contracting party must either own the property or be authorised to dispose of it. A transaction concluded by an unauthorised intermediary (fuḍūlī) is void—unless he buys on credit for an unnamed principal; in that case the sale becomes valid once that principal ratifies it, otherwise the liability rests with the buyer.

Nothing except residential dwellings may be sold in territories that were conquered by force (1), such as the lands of Egypt and Syria [and similar regions] (2); other kinds of property there may only be leased. As for the houses (ribāʿ) of Mecca, they may neither be sold nor rented (3). The water drawn from a well, grazing pasture, and the like may not be sold before they are actually taken into possession; whoever first takes hold of them becomes their owner.

The seller must also be able to deliver the item (4); therefore the sale of a runaway slave, a stray animal, a bird while it is in the air, fish still in the water, or stolen property is invalid—except when sold to the thief himself or to someone capable of reclaiming it from him.

The object of sale must be known, either through inspection or through a description that suffices in a deferred-delivery sale (salam) (5). Hence it is invalid to sell a fetus still in the womb, milk in the udder, musk still inside its pouch (6), or the like; nor may one say, “one of these slaves,” or exclude an item unless it is precisely identified. It is permissible to sell an animal while excluding its head, hide, or limbs, but not to exclude its fat or unborn young (7). It is also valid to sell fava beans while they are still in their pods.