the work; he may be using the term as his opponents use it so as not to provoke an automatic rejection or argument on that particular issue. From the extant fragment of Kitāb al-Īḍāḥ it is evident that many of the akhbār or oral reports that are cited as evidence for particular legal positions are attributed to earlier Imams, especially Muḥammad al-Bāqir (d. 114/732) and Jaʿfar al-Ṣādiq (d. 148/765), and not to the Prophet. In the Ikhtilāf as well, reports going back to the early Imams are cited as evidence, though he does not use the term Sunnah to describe them. There is arguably some conflation of the two categories, on the understanding that the Imams are in many cases reporting material that has been passed down from the Prophet through their forefathers, his descendants. In al-Qāḍī al-Nuʿmān’s work as a whole, one would evidently draw the line between Sunnah and pronouncements of the Imams after Jaʿfar al-Ṣādiq: pronouncements from the Prophet and the Imams up through Jaʿfar al-Ṣādiq, which are available through Shiʿi compilations of law and ḥadīth, especially as compiled in Kitāb al-Īḍāḥ, and the pronouncements of the Fatimid caliph-imams, especially of the current Imam, which are available in other sources or directly from the Imam himself.
The pronouncements of the current Imam represent the third source, and al-Qāḍī al-Nuʿmān makes a significant effort to justify the Imams’ authority, this being understood as that of the Fatimid caliphs. His references to the current caliph, al-Muʿizz li-Dīn Allāh, as well as to the previous caliphs, and his pointed mention of the lifting of dissimulation (taqiyyah) in his time make this clear. In al-Qāḍī al-Nuʿmān’s view, this source is not an extraneous source divorced from the other two but is in fact intrinsic to the Qurʾan and the Sunnah. This is because both the Qurʾan and the Sunnah include unambiguous statements referring to the Imams’ authority. On the whole, this argument resembles al-Shāfiʿī’s argument for the authority of the Sunnah: It is not separate from the Qurʾan because the Qurʾan contains its explicit justification. The chief Qurʾanic prooftexts al-Qāḍī al-Nuʿmān cites are Q Nisāʾ 4:59 and Naḥl 16:43, both of which had become well-known authority verses among both Sunni and Shiʿi scholars by his time. The first includes the statement: aṭīʿū llāha wa-aṭīʿū r-rasūla wa-ulī l-amri minkum «Obey God and obey the Messenger and the Ones in Authority among you.» Al-Qāḍī al-Nuʿmān interprets ulū al-amr “the Ones in Authority” in this verse as an unequivocal reference to the Shiʿi Imams. The second verse includes the phrase, fa-sʾalū ahla dhdhikri in kuntum lā taʿlamūn «So ask the People of Knowledge if you do not know.» Again, al-Qāḍī al-Nuʿmān interprets the phrase ahl al-dhikr “the People of Knowledge” as an unambiguous reference to the Imams. He devotes some effort to justifying this view, arguing against various interpretations proposed by Sunni scholars that identify these phrases as references to the authority of military commanders, rulers, religious scholars, or jurists. Throughout the Ikhtilāf uṣūl al-madhāhib, al-Qāḍī al-Nuʿmān uses these two labels, “the Ones in Authority” and “the People of Knowledge” as technical terms referring to the Imams as the sole legitimate Islamic religious authorities. While he cites a number of other verses as justification for the Imams’ religious authority, these two are decidedly dominant in his discussion.30
Al-Qāḍī al-Nuʿmān also cites oral reports from the Prophet as justification for the Imams’ religious authority. Chief among these is ḥadīth al-thaqalayn “the Report of the Two Weighty Matters,” one of the chief oral reports cited in this fashion in Shiʿi tradition. This text mentions the Book—the Qurʾan—and ahl al-bayt “members of the Prophet’s family” as twin objects to which the believers must cleave after the demise of the Prophet in order to gain salvation. Again, for al-Qāḍī al-Nuʿmān, the term ahl al-bayt in the report is an unambiguous reference to the Imams. Therefore, just as the religious authority of the Imams is part and parcel of the Qurʾan, so too is it part and parcel of the Prophetic Sunnah.
With regard to oral reports, however, there are significant omissions. It is surprising, from the point of view of Sunni-Shiʿi polemics in this period, that al-Qāḍī al-Nuʿmān does not cite the report of Ghadīr Khumm or what is called ḥadīth al-manzilah “the Report of the Status,” two of the best known and most widely cited justifications of the authority of the Shiʿi Imams. According to the first report, the Prophet stopped at the pond of Ghadīr Khumm and addressed the Muslims who were returning with him to Medina after the Farewell Pilgrimage in the final year of his life. In his speech, he stated man kuntu mawlāhu fa-ʿAliyyun mawlāhu “Whoever I am the master of, ʿAlī is his master.” According to the Shiʿi interpretation, the Prophet intended by this the explicit designation of ʿAlī as his successor. In the second report, the Prophet is supposed to have said to ʿAlī that your position with regard to me is like that of Aaron with respect to Moses. Both reports were extremely influential for Twelver Shiʿah and for the Ismaʿilis in particular. They featured prominently in polemics between Sunnis and Shiʿah. On the basis of that first report, both the Fatimids and the Buwayhids instituted a Shiʿi holiday, ʿĪd al-Ghadīr, to be celebrated on the 18th of Dhu l-Hijjah, to mark the Prophet’s explicit designation (naṣṣ) of ʿAlī ibn Abī Ṭālib as his successor.
It is not clear why the report of Ghadīr Khumm does not appear in Ikhtilāf uṣūl al-madhāhib, but there must be a specific reason, since it is so well known and such a major justification of the Imams’ religious authority. Perhaps al-Qāḍī al-Nuʿmān saw that citing the Ghadīr Khumm report would lead directly into disputes about the Imamate in particular, which for this work would be a digression from the main topic. In contrast, in Daʿāʾim al-islām, he discusses Ghadīr Khumm in detail as a justification for allegiance to the Imams and to the Fatimids in particular in the introductory section on walāyah.31 It appears that he must have been writing that already while composing Ikhtilāf uṣūl al-madhāhib, or at least planning to write it, and these omissions are likely relegating detailed debate over the Imamate per se to Daʿāʾim al-Islām and other works.
Along with a presentation of the Ismaʿilī doctrine of religious authority, al-Qāḍī al-Nuʿmān criticizes Sunni views of religious authority, which he sees as having deviated from the truth in two important ways. First, as he describes it, the caliphs of the Sunnis proved their illegitimacy by turning away from religion and focusing single-mindedly on worldly wealth and power. They did not fulfill their duties as Imams of the Muslim community, which include the provision of comprehensive guidance for the believers. Second, Sunni jurists claimed religious authority for which they had no warrant. They arrogated to themselves the right to interpret Islamic law and doctrine and to impose their views on the common people, claiming a superior status. Furthermore, the two phenomena are related. As al-Qāḍī al-Nuʿmān puts it, the Umayyad caliphs (661–750) but more significantly the Abbasid caliphs (750–1258), the Fatimids’ chief ideological rivals, made a pact with the jurists according to which the caliphs would give the jurists free reign to control the religion as long as they gave the caliphs free reign to rule as they wished, both flouting Islamic legal restrictions for themselves and treating the populace tyrannically. They thus violated the sacred trust that God placed in them by appointing them to their position of leadership of the community.
In his view, then, the history of Sunni Islam witnessed the derailment of the proper relationship between jurists and the caliphs. Jurists, including judges, serve as authorities and sources of guidance and reference for the common people, but their authority must remain closely tied to and dependent on the authority of the Imams. The introductory section on walāyah in Daʿāʾim al-islām serves, among other functions, to anchor the law as a whole to the authority of the Imams. It is not a body of rules produced by the collective work of legal scholars in a separate field of human inquiry. Rather, it is a body of rules that derives from the Imams’ interpretations of God’s revealed law. For this reason al-Qāḍī al-Nuʿmān cites so prominently in Ikhtilāf uṣūl al-madhāhib his letter of appointment to the judgeship issued by the Caliph al-Muʿizz li-Dīn Allāh and continually refers to consultation of the Imam on difficult matters. It must be made clear that his authority is subordinate to and dependent on that of the Imam; jurists have no independent authority.