This important work is a source-critical study of a group of traditions (aḥādīth) found in Ibn Isḥāq's Biography (Sīra) of the prophet Muḥammad, widely considered one of the most important early historical texts on the Prophet's life. Through a meticulous isnād-cum-matn analysis, the author reveals that Ibn Isḥāq relied on Muḥammad b. Abī Muḥammad, a hitherto undocumented source of his. Important new light is also shed on problems with Ibn Hishām’s recension of Ibn Isḥāq’s Sīra.

Muslims, Jews and Pagans examines in much detail the available source material on the 'Āliya area south of Medina on the eve of Islam and at the time of the Prophet Muḥammad. It provides part of the necessary background for the study of the Prophet's history by utilizing in addition to the Prophet's biographies, various texts about the history, geography and inhabitants of this area.

‘Abd al-‘Azīz b. Marwān (d. 86/705) reigned as the amīr of Egypt and walī al-‘ahd (heir apparent) to the Islamic caliphate for over 20 years. This book intends to revive this largely forgotten amīr and demonstrate the critical role he played in the formation of the Marwānid dynasty. The founding thesis of this study is that ‘Abd al-‘Azīz was appointed the amīr of Egypt and second heir apparent due to the legitimacy his maternal lineage brought the nascent dynasty.

The present work provides a new edition and substantial German commentary of the important theological Arabic work Al-Tamhīd fī bayān al-tauḥīd (“Introduction to the explanation of monotheism”) by the 5th/11th century scholar Abū Shakūr al-Sālimī. The work and its author belong to the theological school that succeeded Abū Manṣūr al-Māturīdī (died 333/944) and still serve as important markers of Sunnī theology into the nineteenth century.