the exemplar, master memorizer, and decisive authority; together with Sālim and ʿIkrimah he was considered the leading scholar of his time in Madinah. He bore the kunyas Abū Muḥammad and Abū ʿAbd al-Raḥmān, and was a Qurashi of the Taymi branch—one of the Bakr clan—Madinan by residence.
He was born during the caliphate of Imām ʿAlī. His supposed chain “from his father from his grandfather” is doubly broken, for neither of the two actually transmitted from his own father. Al-Qāsim was raised in the care of his aunt, the Mother of the Believers ʿĀʾishah; he studied jurisprudence with her and reported extensively from her.
He related, in mursal form, from Ibn Masʿūd, and likewise mursal from Zaynab bint Jahsh. He also narrated from Fāṭimah bint Qays, Ibn ʿAbbās, Ibn ʿUmar, his grandmother Asmāʾ bint ʿUmays, Abū Hurayrah, Rāfiʿ ibn Khadīj, ʿAbd Allāh ibn Khabbāb, ʿAbd Allāh ibn ʿAmr, Muʿāwiyah, and a number of others, as well as from Ṣāliḥ ibn Khawwāt and from ʿAbd al-Raḥmān and Mujammiʿ, the two sons of Yazīd ibn Jāriyah.
Those who transmitted from him include his son ʿAbd al-Raḥmān, al-Shaʿbī, Nāfiʿ the client of ʿUmar, Sālim ibn ʿAbd Allāh, Abū Bakr ibn Ḥazm, al-Zuhri, Ibn Abī Mulaykah, Saʿd ibn Ibrāhīm, Ḥumayd al-Ṭawīl, Ayyūb, Rabīʿah al-Raʾy, ʿUbayd Allāh ibn ʿUmar, Ibn ʿAwn, Rabīʿah ibn ʿAṭāʾ, Thābit ibn ʿUbayd, Jaʿfar ibn Muḥammad, Yaḥyā ibn Saʿīd al-Anṣārī and his brother Saʿd ibn Saʿīd, Shaybah ibn Niṣāḥ, Ṭalḥah ibn ʿAbd al-Malik, ʿĀṣim ibn ʿUbayd Allāh, Abū al-Zinād, ʿUbayd Allāh ibn Abī al-Zinād al-Qaddāḥ, ʿUmar ibn ʿAbd Allāh ibn ʿUrwah, ʿĪsā ibn Maymūn al-Wāsiṭī, Mūsā ibn Sargis, Aflah ibn Ḥumayd, Ḥanẓalah ibn Abī Sufyān, Usāmah ibn Zayd al-Laythī, ʿAbd Allāh ibn al-ʿAlāʾ ibn Zabr, Ṣāliḥ ibn Kaysān, Ayman ibn Nābil, ʿAbbād ibn Manṣūr, and many others besides.
Ibn al-Madīnī said: “He is credited with two hundred hadiths.”