Narrated Ibn `Abbas: Allah's Apostle entered upon a sick bedouin in whom he went to visit and said to him, Don't worry, Tahur (i.e., your illness will be a means of cleansing of your sins), if Allah Will. The bedouin said, Tahur! No, but it is a fever that is burning in the body of an old man and it will make him visit his grave. The Prophet said, Then it is so.