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In imam: Imamate in Shiʿi Islam
…that the imamate passed to Mūsā al-Kāẓim, another son of Jaʿfar. The strength of this faction was seen in the decision of the Abbasid caliph al-Maʾmūn to name as his heir the faction’s eighth imam, ʿAlī al-Riḍā. This decision was highly controversial from the start, however, and ʿAlī died before…
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In Shiʿi: The growth of Imāmī Shiʿism
…maintained that Jaʿfar’s successor was Mūsā al-Kāẓim, another son of imam Jaʿfar.
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In Islam: Ismāʿīlīs
Instead of recognizing Mūsā as the seventh imam, as did the main body of the Shiʿah, the Ismāʿīlīs upheld the claims of his elder brother Ismāʿīl. One group of Ismāʿīlīs, called Seveners (Sabʿiyyah), considered Ismāʿīl the seventh and last of the imams. The majority of Ismāʿīlīs, however, believed…
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In Jaʿfar al-Ṣādiq
…claimed the imamate; of these, Mūsā al-Kāẓim gained widest recognition. Shiʿi sects not recognizing Ismāʿīl are mostly known as “Twelvers”; they trace the succession from Jaʿfar to the 12th imam, who disappeared and is expected to return at the Last Judgment.
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