The Prophet Muhammad (peace be upon him) said: “There are six good qualities that one believer should display to another. He should visit him when he is ill, be present when he dies, accept his invitation when he gives one, salute him when he meets him, say ‘God have mercy on you’ when he sneezes, and act sincerely towards him whether he is absent or present.”Al-Tirmidhi, hadith 1204.