Ibn Tahir summarizes his opinion of the Mahdi, saying: "Indeed, Imam Mahdi, Abu Abdullah, is the absolute one, the first Imam, and he is the one foretold by his grandfather, may God Almighty and His noble angels bless him and grant him peace. So he was awaited and hoped for."

He began his proofs for this by establishing that the Mahdi is the awaited and hoped-for man, as mentioned in the hadiths concerning the awaited Mahdi. This is because he was able to remove the oppression, tyranny, and rampant misguidance of the Almoravids. He appeared over them, spreading guidance and establishing justice.

By doing so, he "fulfilled the wish to its utmost." The matter, up to this point, flows, progresses, and is inseparable. Everything he brought is what his grandfather, peace be upon him, called for. "Has this not brought a Mahdi? He is truly a Mahdi."

His innate nature, his knowledge of the characteristics of human souls, and his excellence in knowledge—all of this makes him "knowledgeable of intellectual virtues and moral virtues." This is the first Imam who deserves to be the one who guides the universe and whose return is beyond being a servant of any worldly matters, but rather a governor of all, so that true happiness may be achieved for people. This is the great success.

Then he proceeds to prove the congruence of the descriptions mentioned in the hadiths about the awaited Mahdi with Ibn Tumart. He presents a serious objection voiced by the "inclined soul," which says: "Perhaps those qualities [the qualities of the awaited Mahdi] have coincidentally matched. Then the foretold Mahdi, who possesses those qualities, will come in..."