145-No.0440 hadith found in 'The Book of Purification (Kitab Al-Taharah)' of Sahih Muslim.

0440 Humran reported when 'Uthman performed ablution he said: By Allah, I am narrating to you a hadith had there not been this verse in the Book of Allah. I would not have narrated it to you. Verily I heard the Messenger of Allah (may peace be upon him) say: Not a person is there who performed ablution, and did it well, then offered prayer, but his sins (which he committed) were not pardoned between the prayer that he offered and the next one. 'Urwa said: The verse is this:" Those who suppress the clear proofs and the guidance which We have sent down"... to His words:" the Cursers" (ii. 15). 

145-No.0439 hadith found in 'The Book of Purification (Kitab Al-Taharah)' of Sahih Muslim.

0439 This hadith is also narrated on the authority with the same chain of transmitters and in the hadith of Abu Usama the words are:" He who performed the ablution well and then offered the obligatory prayer." 

145-No.0438 hadith found in 'The Book of Purification (Kitab Al-Taharah)' of Sahih Muslim.

0438 Humran. the freed slave of 'Uthman. said: I heard from 'Uthman b. 'Affan and he was in the courtyard of the mosque, when the Mu'adhdhin (announcer of the prayer) came to him at the time of afternoon prayer. So the ('Uthman) called for the ablution water and performed ablution and then said: By Allah, I am narrating to you a hadith. If there were not a verse in the Book of Allah, I would have never narrated it to you. I heard Allah's Messenger (may peace be upon him) say: If a Muslim performs ablution and does it well and offers prayer, all his (sins) daring the period from one prayer to another would be pardoned by Allah. 

145-No.0437 hadith found in 'The Book of Purification (Kitab Al-Taharah)' of Sahih Muslim.

0437 Humran, the freed slave of 'Uthman said: I saw Uthman call for a vessel (of water) and poured water over his hands three times and then washed them. Then he put his right hand in the vessel and rinsed his mouth and cleaned his nose. Then he washed his face three times and his hands up to the elbow three times; then wiped his head, then washed his feet three times. Then he said that the Messenger of Allah (may peace be upon him) had said: He who performed ablution like this ablution of mine and offered two raklahs of prayer without allowing his thoughts to be distracted, all his previous sins would be expiated.