Imam al-Murtaḍā li-Dīn Allāh, Abū al-Qāsim Muḥammad ibn Yaḥyā ibn al-Ḥusayn ibn al-Qāsim ibn Ibrāhīm (may God be pleased with them). He called people to God after the death of his father. When Imam al-Hādī died, he came out to the people, reminded them of God, and offered them condolences — then said:

• Kitāb al-Uṣūl — on divine unity and divine justice
• Kitāb al-Īḍāḥ — on jurisprudence
• Kitāb al-Nawāzil — two parts
• Jawāb Masāʾil al-Mughaffalī
• Jawāb Masāʾil Mahdī
• Kitāb al-Nubuwwa — Prophethood
• Kitāb al-Irāda — Will
• Kitāb al-Mashīʾa — Volition
• Kitāb al-Tawba — Repentance
• Al-Radd ʿalā al-Rawāfiḍ — Refutation of the Rāfiḍa
• Kitāb fī Faḍāʾil ʿAlī ibn Abī Ṭālib — on the merits of the Commander of the Faithful
• Al-Radd ʿalā al-Qarāmiṭa — Refutation of the Qarāmiṭa
• Kitāb al-Sharḥ wa-l-Bayān — three parts
• Kitāb al-Riḍāʿ — Suckling
• Kitāb Masāʾil al-Qudamiyyīn
• Kitāb Masāʾil al-Ḥāʾirīn — Questions of the Perplexed
• Kitāb Tafsīr al-Qurʾān — nine parts
• Kitāb Masāʾil al-Ṭabariyyīn — five parts
• Kitāb Masāʾil Mahdī — four parts
• Kitāb Masāʾil Ibn al-Nāṣir
• Kitāb Masāʾil al-Buyūʿ — Questions on Sales, three parts
• Kitāb Masāʾil ʿAbdullāh ibn Sulaymān
• Jawāb Ibn Faḍl al-Qarmaṭī
• Faṣl al-Murtaḍā
• Kitāb al-Nahy — Prohibition

He died during the days of his brother Imam al-Nāṣir Aḥmad ibn Yaḥyā, in the year 310 AH, at the age of thirty-two years. His grave is at the shrine of his father (may God be pleased with them) in Ṣaʿda.

• Abū Muḥammad al-Qāsim
• Ismāʿīl
• Ibrāhīm
• ʿAlī progeny at Jurjān
• ʿAbdullāh progeny at Daylamān and Yemen
• Mūsā
• Yaḥyā progeny at Daylamān
• Al-Ḥasan progeny at Shīrāz, Ṭabaristān, Aṣbahān, and Aṣfahān
• Al-Ḥusayn progeny at al-Rayy and its districts, al-Ahwāz, and Ṭabaristān
• Al-Qāsim
• ʿĪsā
• Muḥammad