A wager stipulated by both sides is not valid
Question
Question: One student said to another student: “If what I say turns out true, you will feed me sweets to my fill, and if what you say turns out true, I will feed you sweets to your fill.” Thus this wager was made between the two. As it happened, what one of them said turned out correct. Is it now obligatory upon the other student to feed him sweets to his fill? Note: The student whose statement turned out correct was firmly certain that his statement would turn out correct, because he had already seen it once.
Answer
Such a wager is not valid in the Sacred Law, and in this case feeding the sweets is not wajib, as stated in Radd al-Muhtar.
Source: Fatawa Mahmudiyya
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