He heard ḥadīth from Abū Kurayb Muḥammad ibn al-ʿAlāʾ, Muḥammad ibn Ḥarb al-Nashāʾī, al-Ḥusayn ibn Abī Zayd al-Dabbāgh, Muḥammad ibn ʿAmmār al-Rāzī, ʿAmr ibn ʿĪsā al-Ḍubaʿī, Muḥammad ibn Bashshār, Muḥammad ibn ʿAbd Allāh ibn ʿUbayd ibn ʿAqīl, and many other companions of Sufyān ibn ʿUyaynah and Abū Muʿāwiyah al-Ḍarīr.
His journey in search of knowledge took place before 250 AH. He collected traditions, authored works, produced critical analyses, and became proverbial for the breadth of his memory.
Those who narrated from him include Abū Ḥātim ibn Ḥibbān, Abū Isḥāq ibn Ḥamzah, Sulaymān ibn Aḥmad al-Ṭabarānī, Abū ʿAmr ibn Ḥamdān, Abū Bakr ibn al-Muqriʾ, and many others.
Abū ʿAbd Allāh al-Ḥākim said: “I heard Jaʿfar ibn Aḥmad al-Marāghī say: ‘ʿAbdān al-Ahwāzī rejected a ḥadīth that Abū Jaʿfar ibn Zuhayr had presented to him. He went to see him and said, “This is my own source, but where did you get the chain Ibn ʿAwn—from al-Zuhrī—from Sālim?”’ … and he cited the tradition. ʿAbdān kept apologising, saying, ‘O Abū Jaʿfar, I only found the ḥadīth unfamiliar.’”
Al-Ḥāfiẓ Abū ʿAbd Allāh ibn Mandah said: “I have never seen anyone in the world with a better memory than Abū Isḥāq ibn Ḥamzah,” and I heard him declare: “I have never seen anyone in the world with a better memory than Abū Jaʿfar ibn Zuhayr al-Tustarī!”
Abū Jaʿfar himself said, “I have not seen anyone whose memory surpassed that of Abū Zurʿah al-Rāzī.”
Abū Bakr ibn al-Muqriʾ said, “Tāj al-Muḥaddithīn (the Crown of the ḥadīth scholars), Aḥmad ibn Yaḥyā ibn Zuhayr, narrated to us …” and he reported a ḥadīth.
Abū Jaʿfar died in 310 AH; he was in his eighties.
I read to Muḥammad ibn ʿAbd al-Salām al-Tamīmī, on the authority of ʿAbd al-Muʿizz ibn Muḥammad al-Bazzāz: Tamīm ibn Abī Saʿīd and another man informed us, saying: “Abū Saʿd Muḥammad ibn ʿAbd al-Raḥmān al-Kanjurūdhī informed us; Abū ʿAmr Muḥammad ibn Aḥmad al-Ḥīrī informed us; he informed me—”