From when to repeat prayers if a wet dream was not remembered

Question

The imam of a mosque had a wet dream (ihtilam). In the morning he did not remember it, nor did he notice any trace of any kind. After two or three days he happened to see a trace of semen on his trousers (pyjama). Now he is thinking about since when it has been there, and after reflection it became clear that most likely it happened on the second or third night; during this interval the imam led however many prayers, and from time to time another person also led the prayers.

Answer

Repetition of the prayer is not ordered on the basis of mere possibility and doubt. Rather, in the case of doubt the ruling is that janaba is deemed to begin from the [last] sleep before the time he saw the semen on the garment, and it is wajib to repeat whatever prayers he performed after waking.

Source: Fatawa Mahmudiyya

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