Hadith: The five prayers are like a great river running by your door in which you wash five times every day

عَنْ أَبِي هُرَيْرَةَ رضي الله عنه أَنَّهُ سَمِعَ رَسُولَ اللَّهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ يَقُولُ:

«أَرَأَيْتُمْ لَوْ أَنَّ نَهَرًا بِبَابِ أَحَدِكُمْ يَغْتَسِلُ فِيهِ كُلَّ يَوْمٍ خَمْسًا، مَا تَقُولُ ذَلِكَ يُبْقِي مِنْ دَرَنِهِ؟» قَالُوا: لَا يُبْقِي مِنْ دَرَنِهِ شَيْئًا، قَالَ: «فَذَلِكَ مِثْلُ الصَّلَوَاتِ الخَمْسِ، يَمْحُو اللَّهُ بِهِ الخَطَايَا».
[صحيح] - [متفق عليه]

Jābir (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "The five prayers are like a great river running by your door in which you wash five times every day." Abu Hurayrah (may Allah be pleased with him) reported: I heard the Messenger of Allah (may Allah's peace and blessings be upon him) say: "What if there was a river at the door of anyone of you wherein he takes a bath five times daily, would there remain any of his filth?" They said: "Nothing of his filth would remain." He said: "This is similar to the five prayers by means of which Allah erases sins."
Sahih/Authentic. - [Muslim]

Explanation

The Prophet (may Allah's peace and blessings be upon him) likened abstract filth to physical filth. Just as bathing five times a day removes filth, praying five times a day eliminates sins.