What are the requirements for the consideration (reward) in a contest or wager?

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The consideration must be known. This is because it is property within a contract, thus it must be determined, similar to other contracts. Knowledge of the consideration can be established through visual inspection, or by measure and description, as previously detailed. The consideration may be due immediately (hal) or deferred (mu'ajjal), just as in a sale contract. Furthermore, part of the consideration may be immediate while another part is deferred. For example, if it is stipulated that upon winning the contest, the winner receives one dinar immediately and a measure of wheat after one month, this arrangement is permissible and the contest is valid. This is based on the principle that what may be entirely immediate or entirely deferred may be split between immediate and deferred terms, as is the case with the price in a sale. However, the deferred portion, such as the wheat, requires a clear description to render it known.