Selling maize for wheat on credit

Question

Question: Someone gave maize or sweet potato to another person with the intention: “I will take wheat at harvest time.” What is the ruling on this?

Answer

Selling maize or sweet potato on the condition that wheat will be taken in exchange for it at harvest time — that is, fixing wheat as the price and receiving it at harvest time — is not valid.

Source: Fatawa Mahmudiyya

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