What is the extent of permissible use of a rented asset in terms of utility?

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The lessee is permitted to utilize the rented asset to fully realize the agreed-upon benefit, or any benefit less harmful than the agreed-upon one. This ruling is held by Al-Shafi'i and Abu Thawr. If a beast of burden is rented to carry dates, and it is used to carry wheat, it is permissible if the weight is the same, according to the view of Ahmad. Any use that is more harmful or qualitatively different in terms of harm than what was contracted for is not permitted because it constitutes taking more than one's due right or taking something one is not entitled to.