the occurrence of this doubt while he is still praying or after he has finished.
3 – Sound reason confirms this shar‘i maxim, for certainty is stronger than doubt: certainty carries a firm, decisive ruling that cannot be toppled by mere conjecture.
4 – If a person imagines that something nullifying wudu has exited him and becomes unsure whether it truly did, the default ruling is that his purity remains. His ablution is therefore not invalidated, nor may he break off his prayer, until he is certain that something has come out, because certainty is not removed by doubt. Al-Bukhari titled a chapter for this hadith: “Chapter: One does not perform wudu because of doubt until he is sure.”
5 – Wind emitted from the anus—whether accompanied by sound or not—nullifies wudu.
6 – The hadith’s mention of “hearing a sound or perceiving an odour” is simply a way of indicating certainty. If a person neither hears nor smells anything yet becomes certain by some other means, his wudu is invalidated. Those two signs were singled out only because they are the most common.
7 – It is forbidden to leave the prayer without a clear, legitimate reason.
8 – Al-Khattabi said: This hadith is proof for those who obligate the prescribed corporal punishment on anyone from whose mouth the odour of an intoxicant is detected, even if he was not seen drinking, no witnesses testified, and he did not confess.