Darar al-Dabbi was among those who denied the Imamate. He met with Hisham, and he asked him:
-Do you say that Allah is just and does not wrong?
-Yes.
-If Allah ordered the crippled to walk and to struggle in His way, if He ordered the blind to read the Qur’an and books, then do you think that He was just or unjust?
-Allah does not do that.
-We have come to know that He does not do that, but for argument and dispute, if He did that, was He not unjust in His deed, and He required him to perform a duty which he could not perform?
-If He did that, then He would be unjust.
-Tell me about Allah, the Great and Almighty: Has He charged mankind with one religion over which there is no difference, and He does not accept (it) from them unless they perform it just as He has charged them with it?
-Yes.
-Has He given them a proof of the existence of that religion or has He charged with something of whose existence there is no proof, so He is like him who orders the blind to read books and to order the crippled to go to Mesjids and jihad?
Dirar kept silent. He found no way to pass through. This affair made him tired. Then he turned to Hisham and said to him: There should be a proof, and the proof should not be from your companion (i.e., Imam ‘Ali, peace be on him).
Hisham smiled and said to him:
-There is no difference between you and me except in name.
Dirar began saying:
-Surely I want to resort to you in a certain statement.
-Give me!
-How was the Imamate entrusted to (anyone)?
-Just as Allah entrusted the prophethood to (someone).
-Therefore, the Imam is a prophet!
-No. The inhabitants of the heaven charged someone with the prophethood, and the inhabitants of the earth charged someone with the Imamate. So the angels entrusted someone with the prophethood, and the prophet entrusted someone with the Imamate. The two offices are accomplished through the permission of Allah.
-What is the proof for that?
-The compulsion in this respect.
-How is that?
-This statement has three meanings: The first meaning: Allah raised mandatory after the Prophet; He did not require them, nor did He order them, nor did He prohibit them, and they became like beasts of prey and animals on which there is no mandatory. Do you believe in this, Dirar?
-I do not believe in that.
-The second meaning: All the people after the Prophet became religious scholars and had the same level of knowledge just as he had, to the extent that they were in no need of each other. Therefor, they were in need of (someone else) and came to know the truth over which they did not differ. Do you maintain this, Dirar?
-I do not maintain that, but they are in need of someone other than them.
-The second meaning: There should be a great figure whom the Prophet appointed over them, and who did not forget, nor did he commit mistakes, nor did he wrong (them), who was protected from sins, free from offenses, whom they needed, and who was in no need of them.
Direr kept silent before this flowing knowledge supported by rational proofs that were far from argument and discussion. ( Bihar al-Anwar, vol. 11, pp. 291-229.)