ʿAlī ibn al-Madīnī said, “I saw Yaḥyā ibn Saʿīd and ʿAbd al-Raḥmān asking him about the narrations of Hushaym—meaning Abū Jaʿfar. I do not know anyone more knowledgeable about them than he.” (1)

Abū Ḥātim said, “I heard Muḥammad ibn ʿĪsā say: ʿAbd al-Raḥmān and Abū Dāwūd disagreed regarding Hushaym’s ḥadith. One of them said, ‘He used to practice tadlīs (concealed transmission),’ while the other said, ‘He heard it directly.’ They agreed to refer the matter to me, so I informed them of what I had, and they accepted it.” (2)

He (Abū Ḥātim) also said, “Muḥammad ibn al-Ṭabbāʿ, a trustworthy and reliable authority, narrated to us; among the ḥadith scholars I have met, I have never seen anyone who preserved the thematic chapters better than he.” (3)

Ibn Abī Ḥātim stated, “My father was asked about the two sons of al-Ṭabbāʿ. He replied, ‘Muḥammad is dearer to me, although Isḥāq held a higher rank, and Muḥammad is more precise.’” (4)

Abū Dāwūd said, “I heard Muḥammad ibn Bakkār ibn al-Rayyān say, ‘Muḥammad ibn ʿĪsā is the better of the two.’ Abū Dāwūd then remarked, ‘Muḥammad engaged in legal study, memorized roughly forty thousand ḥadiths, and would sometimes employ tadlīs.’” (5)

Al-Nasāʾī and others said, “Reliable.” (6)

Ibn Ḥibbān said, “He was among the most knowledgeable of them concerning Hushaym; Yaḥyā and Ibn Mahdī used to ask him about Hushaym’s ḥadiths.” (7)