An unknown period falls under gharar (excessive uncertainty). It is authentically reported that the Prophet ﷺ forbade transactions involving gharar (1). Moreover, an unknown period leads to dispute and contention, and every condition or contract that entails this is invalidated by the Sacred Law.

If the two parties stipulate an unknown period and conclude the sale on that basis, and we hold that the option is invalid, does the one whose purpose has been frustrated have the right of option?

Yes. We previously stated in the chapter on conditions in sale contracts that every invalid condition which does not invalidate the contract entitles the party who stipulated it to an option if his purpose is frustrated.

His statement, “for a known period, even if lengthy,” means that if, for example, he stipulates an option period of one month, one year, or two years, there is no objection.

If someone were to say: This condition is not found in the Book of Allah, because it entails making a binding contract non-binding. If the option period were one month, for example, either party could rescind; thus, it conflicts with the basic implication of the contract and is therefore invalid.

The answer is that the Prophet ﷺ permitted the contracting parties to waive the option of the meeting. Waiving the option of the meeting shortens the period during which the contract remains non-binding, whereas this extends that period. There is no difference between extending and shortening it. Indeed, it may be said that extending it is more considerate of the contracting parties than depriving them of something that belongs to them.

The apparent meaning of the author’s words is that this applies even to something that may perish before the end of the period, such as