(7) باب اسْتِحْبَابِ الْقَوْلِ مِثْلَ قَوْلِ الْمُؤَذِّنِ لِمَنْ سَمِعَهُ ثُمَّ يُصَلِّي عَلَى النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ثُمَّ يَسْأَلُ اللَّهَ لَهُ الْوَسِيلَةَ
Sa'd b. 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."
Reference: Sahih Muslim 386
In-book reference: Book 4, Hadith 15
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 749