Sunan Abi Dawud 176
سنن أبي داود#176SahihAbbad b. Tamim reported from his uncle that a person made a complaint to the Prophet (ﷺ) that he entertained (doubt) as if something had happened to him which had rendered his ablution invalid. He (the Prophet) said:He should not cease (to pray) unless he hears a sound or perceives a smell (of passing wind)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih Bukhari (137) Sahih Muslim (361)
In-book reference: 1:176