It was narrated that ‘Amir bin Sa"d bin Abi Waqqas said: I heard Sa"d and some of the Companions of the Messenger of Allah (ﷺ) say:

There were two men, who were brothers, at the time of the Messenger of Allah (ﷺ), one of whom was better than the other. The one who was the better of the two died; the other outlived him for forty days, then he died too. The superiority of the one who died first over the other was mentioned to the Messenger of Allah (ﷺ), and he said: “Did he (the other one) not pray?" They said: Yes, O Messenger of Allah; there was nothing wrong with him. He said: "You do not know where his prayer took him." Then he said: “The likeness of the prayer is that of a river flowing by the door of a man, deep and fresh, and he immerses himself in it five times every day, Do you think any dirt would be left on him?”