“After the death of Ali bin al-Husayn (Imam as-Sajjad) (as), I went to Abu Ja’far al-Baqir (as). I said to him: “May I die for you! You know that I have kept to your father, felt so happy when being with him and left people aside.” He said: “O Abu Khalid, that is right. What do you want then?” I said: “May I die for you! Your father has described to me the man of this matter (al-Qa’im) in a way that if I see him anywhere, I shall catch his hand.” He said: “Then what do you want?” I said: “I want you to name him so that I shall know him by the name.” He said: “O Abu Khalid, by Allah you asked a so difficult question. You asked me about something that I have never told anyone of. If I have told someone of that, I shall have told you. You asked about something that if the Prophet’s progeny themselves have known it, they will have tried their best to hide it.”