ʿUthmān ibn Abī Shaybah once said, “Al-Asad narrated to us.” Someone asked, “Who is that?” He replied, “Abū Nuʿaym.” (1)

Abū Ḥātim said, “I asked ʿAlī, ‘Who are the most reliable companions of al-Thawrī?’ He answered, ‘Yahyā, ʿAbd al-Raḥmān, Wakīʿ, and Abū Nuʿaym.’ (2)

Al-ʿIjlī stated: “He is trustworthy, firmly grounded in ḥadīth.”

Abū Ḥātim also said, “He is reliable; he preserves the ḥadīth of al-Thawrī and Misʿar with great accuracy. He estimated al-Thawrī’s narrations at about 3,500 and those of Misʿar at roughly 500. He would transmit al-Thawrī’s ḥadīth in the very same wording, never altering it. He could not be prompted, and he was a memorizer of exacting precision.” (3)

From Abū Nuʿaym himself: “Ibn al-Mubārak examined my notebooks and remarked, ‘I have never seen books more accurate than yours.’” (4)

Abū Sahl ibn Ziyād said, “I heard al-Kudaymī say, ‘I heard Abū Nuʿaym declare, “My astonishment has only grown at ʿĀʾishah’s words, ‘Those in whose company one could live have gone,’ (5) but I would rather say:
The people have departed and become scarce, while we remain
a mere remnant amid the vilest riff-raff.”’”