Muḥammad b. Mūsā b. al-Mutawakkil narrated to us, saying that ʿAlī b. al-Ḥusayn al-Saʿdābādī narrated to him among others, from Aḥmad b. Abī ʿAbd Allāh, from his father, from Muḥammad b. Sinān, from al-Mufaḍḍal b. ʿUmar, from al-Ṣādiq, Jaʿfar b. Muḥammad عليه السلام, who said: “Islam is built on five pillars—upon prayer, the obligatory alms-tax, fasting, the pilgrimage (to the Kaaba in Mecca) and the Divine authority of Amīr al-Muʾminīn and the Imams from among his progeny صلوات الله عليهم.”