I said to Abu Abdullah as-Sadiq (as): “With what will the imam (al-Mahdi) be recognized?” He said: “With calmness and gravity.” I said: “What else?” He said: “You will know him by (executing) halal and haram (permissibility and impermissibility), by the need of people to him whereas he will never need any one and that the weapon of the Prophet (S) will be with him.” I said: “Is he a guardian and a son of a guardian?” He said: “He is not but a guardian and a son of a guardian.”