Sahih al-Bukhari 528
Sahih al-Bukhari · Book 9: Times of the Prayers · The five Salat (prayers) are expiations (of sins)
Narrated Abu Huraira:
حَدَّثَنَا إِبْرَاهِيمُ بْنُ حَمْزَةَ ، قَالَ حَدَّثَنِي ابْنُ أَبِي حَازِمٍ ، وَالدَّرَاوَرْدِيُّ ، عَنْ يَزِيدَ ، عَنْ مُحَمَّدِ بْنِ إِبْرَاهِيمَ ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ ، عَنْ أَبِي هُرَيْرَةَ ، أَنَّهُ سَمِعَ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " أَرَأَيْتُمْ لَوْ أَنَّ نَهَرًا بِبَابِ أَحَدِكُمْ، يَغْتَسِلُ فِيهِ كُلَّ يَوْمٍ خَمْسًا، مَا تَقُولُ ذَلِكَ يُبْقِي مِنْ دَرَنِهِ ". قَالُوا لاَ يُبْقِي مِنْ دَرَنِهِ شَيْئًا. قَالَ " فَذَلِكَ مِثْلُ الصَّلَوَاتِ الْخَمْسِ، يَمْحُو اللَّهُ بِهَا الْخَطَايَا " .
I heard Allah's Messenger (ﷺ) saying, "If there was a river at the door of anyone of you and he took a bath in it five times a day would you notice any dirt on him?" They said, "Not a trace of dirt would be left." The Prophet (ﷺ) added, "That is the example of the five prayers with which Allah blots out (annuls) evil deeds."