What is the extent to which a lessee (Musta'jir) may strike an animal under lease?

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The lessee is permitted to strike the animal to the extent customary for its movement, restrain it with a bridle for proper management, and urge it forward to catch up with a caravan. It has been authentically established that the Prophet, peace be upon him, prodded and struck Jabir's camel. Abu Bakr, may Allah be pleased with him, used to prod his camel with his curved stick. This action is considered part of the contract's allowance. Malik, Al-Shafi'i, Ishaq, Abu Thawr, Abu Yusuf, and Muhammad hold that if the damage results from such permissible striking, no liability is incurred.