Abu'l-Fawaris Ahmad ibn Ya'qub was an early 11th-centuryIsma'ili scholar and missionary (da'i) active inSyria, which at the time was largely under the rule of theFatimid Caliphate.^[1] Abu'l-Fawaris was active in the reign of the Fatimid imam-caliphal-Hakim (r. 996–1021),[2] and a contemporary of the fellow Isma'ili scholars,Ahmad ibn Ibrahim al-Naysaburi andHamid al-Din al-Kirmani. All three elaborated Isma'ili ideas about theImamate, apparently independently, since they do not cite each other's works.^[3]

Abu'l-Fawaris' only known work is theRisāla fi’l-imāma ('Epistle on the Imamate'), likely composed before 1017, is divided in sixteen chapters, deliberately chosen to correspond with al-Hakim being the sixteenth Isma'ili imam.^[2] In it, Abu'l-Fawaris argues about the existence of the imamate as a necessity, as theQuran, thesharia (the body of Islamic law) and thesunnah (the traditions ascribed to Muhammad) are not sufficient.^[2] The treatise has been published in a critical edition with English translation bySami N. Makarem asThe Political Doctrine of the Ismāʿīlīs: The Imamate. Caravan Books, Delmar, New York, 1977.^[4]

• Lalani, Arzina R. (2010).Degrees of Excellence: A Fatimid Treatise on Leadership. A new Arabic edition and English translation of Aḥmad b. Ibrāhīm al-Naysābūrī'sKitāb ithbāt al-imāma. London and New York: I. B. Tauris.ISBN 978-1-84511-145-8.

• 11th-century Arabic-language writers
• 11th-century Ismailis
• 11th-century people from the Fatimid Caliphate
• Ismaili theologians
• Medieval Islamic philosophers
• Syria under the Fatimid Caliphate

• Year of birth unknown
• Year of death unknown