They said: Must we look for a miracle, or are they shy and insist on demanding proof from tradition or reason? When they are answered with one of the two proofs, the cycle is necessitated.

And when it was so, this questioner does not look into his question to answer it, because of what results from the cycle. Rather, he looks at the case where he is an infidel or a monotheist.

If he is an infidel, there is no discussion with him until he knows monotheism and proves divinity. Then, when he proves divinity and knows monotheism, he is either stubborn or seeking guidance. If he is stubborn, his conversation is dropped. If he is seeking guidance, he is told: Know that God Almighty willed in His eternity to send a messenger to some of His servants and to reveal judgments and laws through him.

This messenger, and commanded him to convey His judgments. He said: O Lord, the people to whom You sent me do not know the truth of what I say. He said: Your duty is only to convey, and I will reveal through you a sign that proves your truth. So the messenger conveyed these judgments, and their obligation was established by God Almighty, according to what He willed and intended. So the creation has no excuse to reject them.

This explanation from the Mahdi is, in reality, an answer that looking into the miracle is from the Sharia.

And with that, he has answered the question that was mentioned earlier as leading to impossibility, and thus he fell into contradiction. Furthermore, the questioner's neglect of the infidel and his exclusion from the address in this context is a matter of concern, because the infidel is the one addressed by the miracle to believe in the truth of the messenger in his judgments, among which, and the basis of which, is monotheism. Unless the Mahdi is among those who believe in the obligation to know God according to reason even before the advent of the Sharia. However, we have not found any explicit statement from him to that effect.

(Risala fi al-'ibada - Ibn Tumart)