2. The second category includes anything that overpowers one’s consciousness: fainting, deep sleep, intoxication, or an epileptic seizure. Light drowsiness that neither clouds nor overwhelms the mind does not nullify ablution; but once a person lapses into heavy sleep, wudu becomes obligatory. A person who remains seated upright, or who sits clasping his knees, is rarely overtaken by such deep sleep.

The proof that sleep requires a new ablution is the Messenger of Allah’s statement: “When one of you rises from sleep, let him not dip his hand into the water for wudu.” This indicates that the one who awakens from sleep must perform wudu. Zayd ibn Aslam, commenting on the Almighty’s words, “O you who believe, when you rise for prayer…” (Qur’an 5:6), said: “It means: when you rise from your beds,” that is, after sleeping. Safwān ibn ‘Assāl likewise reported: “The Messenger of Allah commanded us not to remove our leather socks because of defecation or urination, but only because of janābah (major ritual impurity).” In this report he placed sleep on the same footing as urine and feces.