First: The conditions agreed upon by the sects of Ahl al-Sunnah, the Mu'tazila, and the Khawarij return to two fundamental pillars: The first is reaching a degree of knowledge that qualifies for ijtihad in the principles and branches of religion. The second is reaching a degree of justice that encompasses the qualities of piety, guidance in matters of politics, and good management of people's affairs. These two pillars perfectly correspond to the two criteria upon which infallibility was based for al-Mahdi. These are: infallibility from falsehood, which corresponds to knowledge, and infallibility from injustice, which corresponds to justice. This agreement in the criteria for infallibility for Ibn Tumart and the criteria for the conditions for the aforementioned sects is evidence for what we have mentioned.

Second: Ibn Tumart sometimes attributed infallibility to the Mahdi and sometimes to the Imam without qualification. We have previously stated that he placed the four Rightly Guided Caliphs in the chain of Imams, so these would be included in the infallibility he generally attributed to the Imam. It is unlikely that he attributed infallibility to them in the Shi'ite sense, as he spoke at length about Abu Bakr and Umar specifically without any indication of this, near or far. Yet, he described them with all the qualities of justice, chastity, and good conduct, which serves as evidence that he did not intend the Shi'ite meaning of infallibility.

Third: We have not found in the writings of al-Mahdi a definition of the reality of infallibility or an explanation of its elements. Rather, he affirmed it for the Imam without explanation or definition. This allows us to assume that he used infallibility in its linguistic sense, which is prevention. Thus, his assertion that the Imam can only be infallible from falsehood and injustice meant that he can only be prevented from falsehood and injustice. In this case, the meaning of infallibility for al-Mahdi approaches the meaning of requiring knowledge and justice among the other sects. However, the use of the word "infallibility" with insistence...

(See the conditions of the Imam in: Qadi Abd al-Jabbar, Al-Mughni: 201, 92, and subsequent pages, 208 and subsequent pages. Al-Baghdadi, Usul al-Din: 277. Al-Aydi and Al-Lahraji, Al-Mawaqif wa Sharhuhu: 383. Al-Amidi, Ghayat al-Maram: 248-249. See: Ibn Tumart, Kitab al-Imamah: 2531.)