Sleep Nullifies Wudu, Not Lying Down

Question

It is written in a book of rulings (masa’il) that wudu is broken by lying on one’s back or on one’s side. Is it broken merely by lying on one’s back or side, or is it necessary that sleep comes?

Answer

Wudu is not broken merely by lying down, whether one lies on one’s back or on one’s side; wudu is broken by falling asleep, whether the sleep came while on one’s side or on one’s back.

Source: Fatawa Mahmudiyya

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