Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said, “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 said, “That is the example of the five prayers with which Allah erases evil deeds.”

Source: Sahih Bukahri 505, Sahih Muslim 667

Grade: Muttafaqun Alayhi (authenticity agreed upon) according to Al-Bukhari and Muslim

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 

صحيح البخاري كِتَاب مَوَاقِيتِ الصَّلَاةِ بَاب الصَّلَوَاتُ الْخَمْسُ كَفَّارَةٌ 505

667 صحيح مسلم كتاب المساجد ومواضع الصلاة باب المشي إلى الصلاة تمحى به الخطايا وترفع به الدرجات