"I was waliking with the Messenger of Allah and he passed by the graves of the Muslims and aid: 'They died before a great deal of evil came to them.' Then he passed by the grave of the idolators and said: 'They died before a great deal of good came to them.' Then he rurned, and he saw a man walking between the graves in his sandals and he said; 'O you with the Sibtiyah sandals, take them off"'. (Shahih)