'Abbad b. Tamim reported from his uncle that a person made a complaint to the Apostle (ﷺ) that he entertained (doubt) as it something had happened to him breaking his ablution. He (the Holy Prophet) said
He should not return (from prayer) unless he hears a sound or perceives a smell (of passing wind). Abu Bakr and Zuhair b. Harb have pointed out in their narrations that it was 'Abdullah b. Zaid.
Abu Huraira reported
The Messenger of Allah (ﷺ) said: If any one of you has pain in his abdomen, but is doubtful whether or not anything has issued from him, be should not leave the mosque unless he hears a sound or perceives a smell.