Jaʿfar ʿAbd Allāh ibn Muḥammad ibn ʿAbd Allāh ibn Jaʿfar ibn Yamān al-Juʿfī, their client, a native of Bukhara—better known as “al-Musnadi” because of his tireless devotion to musnad hadiths.
He journeyed far and wide, taking knowledge from Sufyān ibn ʿUyaynah, Marwān ibn Muʿāwiyah, Isḥāq al-Azraq, Fuḍayl ibn ʿIyāḍ, ʿAbd Allāh ibn Numayr, ʿAbd al-Razzāq, and their tier of scholars.
Those who narrated from him include al-Bukhārī in his Ṣaḥīḥ, al-Dhuhli, Abū Zurʿah al-Rāzī, ʿUbayd Allāh ibn Wāṣil, the jurist Muḥammad ibn Naṣr, and many others from that region.
Abū Ḥātim said: “Reliable.” (1)
Al-Ḥākim stated: “He was, without dispute, the foremost hadith authority of his time in Transoxiana, and he was al-Bukhārī’s teacher.”
I say: al-Bukhārī’s grandfather embraced Islam at the hands of Yamān, the Musnadi’s grandfather.
Ghunjar narrates in his History, with his chain of transmission, that al-Bukhārī said:
“Al-Ḥasan ibn Shujāʿ said to me, ‘How could any hadith elude you when you have stumbled upon a treasure!’—meaning al-Musnadi.” (2)
Al-Musnadi passed away in Dhū al-Qaʿdah, 229 AH. He was in his nineties.
Aḥmad ibn Sayyār said: “Abū Jaʿfar left his homeland and remained abroad in pursuit of hadith.”