It is narrated from ‘Amir bin Sa’d bin Abi Waqqas, he says: I heard from Sayyiduna Sa’d (may Allah be pleased with him) and also from some other companions, they used to say: In the time of the Messenger of Allah (peace and blessings be upon him), there were two men who were brothers, and one of them was superior to the other, and he passed away. After him, the other brother lived for another forty days and then died. But when the superiority of the one who died first was mentioned to the Messenger of Allah (peace and blessings be upon him) over the other, he (peace and blessings be upon him) said: Did the second one not offer (forty days of) prayers? The companions said: Yes, O Messenger of Allah! There is no objection to that (meaning he was also a good man). The Prophet (peace and blessings be upon him) said: Do you know to what extent those prayers have elevated him? Then the Prophet (peace and blessings be upon him) said: The example of prayer is like that of a flowing river, deep enough to drown in, with sweet water, and it is at the door of one of you, and he enters it five times a day (i.e., bathes in it). What do you think, will it leave any dirt or filth on him?