The Prophet ﷺ said, "There is no need for ablution except after passing wind or relieving oneself."
حدثنا محمد بن جعفر حدثنا شعبة قال سهيل بن أبي صالح يحدث عن أبيه
عن النبي ﷺ أنه قال لا وضوء إلا من حدث أو ريح
No references are available.
Its isnad is sahih. Tirmidhi reported it, 1/109, no. 74, in the chapter on wudu, on what has been said about wudu due to passing wind, and he said, hasan sahih. Ibn Majah also reported it, 1/172, no. 515, in the chapter on wudu, on there being no wudu except due to hadath, as did Bayhaqi, 1/117, 220.