Is the disposition of an authorized slave valid beyond the scope of the permission granted?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
The disposition of an authorized slave is valid only within the limits of what he was permitted to do. This is the established position of Ahmad and Ash-Shafi'i. There is no known disagreement on this point, and any action exceeding the permission is invalid.
Supporting text
Abu Hanifa held that if a slave is permitted in one category of transaction, the restraint is lifted entirely, and he is authorized to transact absolutely because restraint cannot be partially lifted. The proof against this view is that the authorized person acts by permission, so his actions are confined to the scope of the permission, like an agent (wakeel). Furthermore, the assertion that restraint cannot be divided is incorrect, as permission to sell one specific item while being prohibited from selling another is permissible, similar to agency in buying.