Hadith 232
Humran, the freed slave of 'Uthman bin 'Affan, reported on the authority of 'Uthman bin 'Affan that he heard Allah's Messenger (ﷺ) say: He who performed ablution for prayer and performed it properly and then went (to observe) obligatory prayer and offered it along with people or with the congregation or in the mosque, Allah would pardon his sins.
Hadith 386
Sa'd bin Abu Waqqas reported: The Messenger of Allah (ﷺ) said: If anyone says on hearing the Mu'adhdhin: I testify that there is no god but Allah alone. Who has no partner, and that Muhammad is His servant and His Messenger, (and that) I am satisfied with Allah as my Lord, with Muhammad as Messenger. and with Islam as din (code of life), his sins would be forgiven. In the narration transmitted by Ibn Rumh the words are: "He who said on hearing the Mu'adhdhin and verity I testify." ' Qutaiba has not mentioned his words: "And I."