Scholarly Reception and Influence on the Study of Religions and Islamic Theology

Al-Milal wan-Nihal achieved a place of recognized authority in the Islamic scholarly tradition almost immediately following its completion. Later scholars drew on it both for its account of Islamic theological schools and for its summaries of non-Islamic traditions, treating it as a reliable reference even when they added to or corrected it.

Ibn Hazm al-Andalusi (d. 456 AH/1064 CE) had produced his own comparative religious work Al-Fisal before ash-Shahrastani wrote, and a comparison between the two works reveals different approaches: Ibn Hazm's work is more polemical and more narrowly focused on refuting deviations from what he considered correct doctrine, while ash-Shahrastani's is more encyclopedic and descriptive. Later scholars who needed both approaches drew on both works.

Ibn Khaldun (d. 808 AH/1406 CE) cited Al-Milal wan-Nihal in his Muqaddimah, drawing on ash-Shahrastani's classifications in his own discussion of Islamic theological schools. This endorsement by the towering intellectual historian of medieval Islam confirmed the work's authority.

In Western Islamic studies, Al-Milal wan-Nihal attracted early scholarly attention as a primary source for medieval Islamic theology and comparative religion. A German translation by Theodor Haarbrücker (1850–1851) was one of the earliest European translations of a major Islamic theological work and introduced ash-Shahrastani to European scholars. This translation made the work accessible to the comparative religion scholarship of the nineteenth century, which was attempting to map the world's religious traditions.

Modern critical editions include the edition by Muhammad Sayyid Kilani (Cairo, 1961) and the well-regarded edition by Ahmad Fahmi Muhammad (Beirut), both of which are used in contemporary academic research. A partial English translation by A.K. Kazi and J.G. Flynn covers significant portions of the work.

In contemporary Islamic scholarship, Al-Milal wan-Nihal remains valuable for students of Islamic intellectual history, comparative religion, and the history of Islamic theology. Its systematic approach to classification and its aspiration toward objective description — unusual for its time — make it a methodological model as well as a historical source.