A sleeping partnership that is based on the owner giving the worker permission to trade with his property (al‑muḍārabah al‑idhniyyah) is not one of the irrevocable (lāzim) contracts [in Islamic law], meaning that the owner can revoke the permission he gave to the worker to use his property. Similarly, the worker is not obliged to continue doing the work with the owner’s capital.
Whenever he wishes, he can refrain from doing the work; this may be before starting the work or after it, or it may be before profits become evident or after it. Furthermore, the worker can do this whether the contract is non-specific about its duration or it specifies the duration. However, if the two parties stipulate a condition that they will not annul the contract until a specified time, then the condition is valid and it is obligatory (wājib) on them to act according to it.
But, in case one of them does annul, the contract will be considered annulled even though the person will have committed a sin by acting contrary to his undertaking.