ʿAbū ʿAbdallāh Muḥammad b. Ibrāhīm b. Jaʿfar al-Nuʿmānī (d. 360/971), also known as Ibn Abī Zaynab, called “al-Kātib” (the secretary), was an Imāmī Shīʿī traditionist, a Qurʾānic exegete, and an important contributor to the development of the doctrine of the ghayba (occultation) of the Twelfth Shīʿī Imām in 260/874. The disappearance under mysterious circumstances of the twelfth spiritual leader of the Shīʿī community, Muḥammad al-Mahdī, had to be explained over time to the faithful in doctrinal terms. The doctrine as developed postponed the return (rajʿa) of the Imām to the en…