- Al-Khallāl — Abū Bakr Aḥmad ibn Muḥammad ibn Hārūn
The imam, eminent scholar, ḥāfiẓ and jurist; the leading teacher and authority of the Ḥanbalīs: Abū Bakr Aḥmad ibn Muḥammad ibn Hārūn ibn Yazīd al-Baghdādī, widely known as al-Khallāl.
He was born in 234 AH, or perhaps in 235 AH; hence it is conceivable that he actually met Imām Aḥmad. He nevertheless learned fiqh from many of the Imam’s companions and became a foremost pupil of Abū Bakr al-Marwadhī.
He heard ḥadith from al-Ḥasan ibn ʿArafah, Saʿdān ibn Naṣr, Yaḥyā ibn Abī Ṭālib, Ḥarb ibn Ismāʿīl al-Kirmānī, and Yaʿqūb ibn Sufyān al-Fasawī—whom he met in Fars—as well as Aḥmad ibn Mulāʿib, al-ʿAbbās ibn Muḥammad al-Dūrī, Abū Dāwūd al-Sijistānī, ʿAlī ibn Sahl ibn al-Mughīrah al-Bazzār, Aḥmad ibn Manṣūr al-Ramādī, Abū Yaḥyā Zakariyā ibn Yaḥyā al-Nāqid, Abū Jaʿfar Muḥammad ibn ʿUbayd Allāh ibn al-Munādī, ʿAbd Allāh ibn Aḥmad ibn Ḥanbal, al-Ḥasan ibn Thawwāb al-Mukhrimmī, Abū al-Ḥasan al-Maymūnī, Ibrāhīm ibn Isḥāq al-Ḥarbī, Muḥammad ibn ʿAwf al-Ṭāʾī, Isḥāq ibn Sayyār al-Naṣībī, Abū Bakr al-Ṣāghānī, and many others.
He travelled through Fars, Greater Syria, and the Jazīrah seeking Imām Aḥmad’s legal judgments, verdicts, and replies. He recorded from scholars great and small—even from the Imam’s own students—gathering an unparalleled collection. From this material he compiled al-Jāmiʿ fī al-Fiqh (The Comprehensive Book on Jurisprudence), consisting of the Imam’s statements introduced with the words “He informed us” and “He narrated to us,” filling twenty volumes. He also produced al-ʿIlal (Hidden Defects) from the teachings of Aḥmad