Abdur Rahman I. Doi stands among the most authoritative English-language scholars of Islamic jurisprudence to emerge from the twentieth century. His scholarship is distinguished by a rare combination of traditional 'ilm ? deep grounding in the Qur'an, Sunnah, and the classical fiqh tradition ? with rigorous exposure to comparative and international legal systems acquired at some of the world's foremost institutions.

Professor Doi's intellectual formation began with immersion in Islamic sciences, including intensive study of the Holy Qur'an and its legal dimensions. His scholarly trajectory took him to Cambridge University, where he conducted research in fiqh (Islamic positive law) and usul al-fiqh (the principles and sources of Islamic jurisprudence). This period, by his own account, proved transformative: confronting fashionable modern critiques of Islamic law, he came to a settled scholarly conviction in the coherence, depth, and moral superiority of the divine legal system over purely human legal constructs. He writes in the preface to this work: "it soon began to dawn upon me that this legal system based on divine guidance has immense potentialities to check the evils which beset the world today."

He pursued further legal studies in England and continental Europe ? at the Inns of Court, Middle Temple in London, at the Hague Academy of International Law in the Netherlands, and at the Université Internationale de Sciences et Droit Comparé in Luxembourg ? subjecting his conclusions to ongoing comparative scrutiny with Western legal scholars. Visits to Imam Muhammad bin Saud University in Riyadh and engagement with leading Arabic-language primary sources further deepened his command of the classical tradition.

The greater part of Professor Doi's career was spent at Ahmadu Bello University, Zaria, Nigeria, where he served as Director of the Centre of Islamic Legal Studies and held a position in the Faculty of Law. It was here that Shari'ah: The Islamic Law took shape, developed from lectures delivered to students of Islamic law and refined over years of teaching and research. The book's ambition ? to present Shari'ah not as "Anglo-Muhammadan Law" mediated through colonial courts but as a living divine system rooted in its primary sources ? reflects Professor Doi's conviction that authentic Islamic legal education must begin with the Qur'an and Sunnah themselves.

Among his other major contributions is Non-Muslims under Shari'ah (Maryland, 1980), which examines the rights and legal status of non-Muslim citizens and residents under Islamic governance ? a subject he addresses with equal thoroughness in the final parts of Shari'ah: The Islamic Law.

Professor Doi's scholarship speaks across institutional contexts: it is at once accessible to students new to Islamic law, substantive enough for advanced researchers in Islamic studies and comparative jurisprudence, and practically valuable for legal practitioners in Muslim-majority contexts. His legacy is a body of work that upholds the dignity and intellectual seriousness of the Islamic legal tradition in the English-speaking world.