Book of Sales
Introduction
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The Book of Sales

A sale is the perpetual exchange of property—even when the property is a debt—or of a permissible usufruct, such as a right of passage, for something of the same category, provided the transaction is neither usury nor a loan.

The contract is concluded by offer and acceptance, whether the acceptance follows the offer, precedes it, or is delayed1 within the same session. If the parties busy themselves2 with something that breaks the session3, the contract is void. This is the verbal formula; it may likewise be effected by muʿāṭāt (mutual delivery), which is the non-verbal form.

Mutual consent is required, so a sale extracted from someone who is unjustly coerced is invalid. The contracting party must also be legally competent; thus the transaction of a minor or a spendthrift without the guardian’s permission is invalid.

The subject matter must be of lawful benefit in itself, not merely in cases of necessity—for example a mule, a donkey, silkworms and their cocoons, an elephant, or beasts of prey suitable for hunting—except for the dog, insects, a copy of the Qur’an, carrion, impure manure, impure oils, and oils that have become contaminated. Such oils may nevertheless be used for lighting, provided it is not in a mosque.

The seller must be the owner of the property or someone acting on his behalf. If a person sells another’s property, or buys something4 with the other’s actual money without his permission, the sale is invalid. If, however, he purchases for him on credit without