Sahih Bukhari

Allah's Messenger (ﷺ) said, "The prayer of a person who does Hadath (passes urine, stool or wind) is not accepted till he performs the ablution." A person from Hadaramout asked Abu Huraira, "What is 'Hadath'?" Abu Huraira replied, " 'Hadath' means the passing of wind."

Once I went up the roof of the mosque, along with Abu Huraira. He perform ablution and said, "I heard the Prophet (ﷺ) saying, "On the Day of Resurrection, my followers will be called "Al-Ghurr-ul- Muhajjalun" from the trace of ablution and whoever can increase the area of his radiance should do so (i.e. by performing ablution regularly).' "

My uncle asked Allah's Messenger (ﷺ) about a person who imagined to have passed wind during the prayer. Allah' Apostle replied: "He should not leave his prayers unless he hears sound or smells something."

Ibn `Abbas said, "The Prophet (ﷺ) slept till he snored and then prayed (or probably lay till his breath sounds were heard and then got up and prayed)." Ibn `Abbas added: "I stayed overnight in the house of my aunt, Maimuna, the Prophet (ﷺ) slept for a part of the night, (See Fath-al-Bari page 249, Vol. 1), and late in the night, he got up and performed ablution from a hanging water skin, a light (perfect) ablution and stood up for the prayer. I, too, performed a similar ablution, then I went and stood on his left. He drew me to his right and prayed as much as Allah wished, and again lay and slept till his breath sounds were heard. Later on the Mu'adh-dhin (call maker for the prayer) came to him and informed him that it was time for Prayer. The Prophet (ﷺ) went with him for the prayer without performing a new ablution." (Sufyan said to `Amr that some people said, "The eyes of Allah's Messenger (ﷺ) sleep but his heart does not sleep." `Amr replied, "I heard `Ubaid bin `Umar saying that the dreams of Prophets were Divine Inspiration, and then he recited the verse: 'I (Abraham) see in a dream, (O my son) that I offer you in sacrifice (to Allah)." (37:102) (See Hadith No. 183)