Narrated Abu Huraira: Allah’s Apostle said, “The prayer of a person who does Hadath (passes urine, stool, or wind) is not accepted till he performs (repeats) the ablution.” A person from Hadaramout asked Abu Huraira, “What is ‘Hadath’?” Abu Huraira replied, ” ‘Hadath’ means the passing of wind from the anus.”
Sahih Bukhari 1:4:137
Narrated Anas bin Malik: Whenever Allah’s Apostle went to answer the call of nature, I along with another boy used to accompany him with a tumbler full of water. (Hisham commented, “So that he might wash his private parts with it.)”
Sahih Bukhari 1:4:152, See also: Sahih Bukhari 1:4:153
Narrated Anas bin Malik: Whenever Allah’s Apostle went to answer the call of nature, I along with another boy used to carry a tumbler full of water (for cleaning the private parts) and an ‘Anza (spear-headed stuck [sic]).
Sahih Bukhari 1:4:154
Note: The above hadith should say ‘spear-headed stick’.
Narrated AbuHurayrah: The Prophet (peace be upon him) said: The following verse was revealed in connection with the people of Quba’: “In it are men who love to be purified” (ix.108). He (AbuHurayrah) said: They used to cleanse themselves with water after easing. So the verse was revealed in connection with them.
Abu Dawud 1:44