“I heard the Messenger of Allah (ﷺ) say: ‘Do you
think
that if there was a river in the courtyard of anyone of you, and
he
bathed in it five times each day, would there be any dirt left on
him?’ They said: ‘(There would be) nothing.’ He said: ‘Prayer
takes
away sins like water takes away dirt.’”
Sunan Ibn Majah Book 5, Hadith 595