Abu Ahmad ibn Adi al-Jurjani: Abu al-Zunad was one of the Faqihs of the people of Medina, their Muhaddith (hadith scholar), and narrator of their reports. The Imams narrated from him, such as Malik and Thawri and others. His hadiths are all upright, and he is, as Ibn Ma'in said, trustworthy, an authority.
Abu Hatim al-Razi: Trustworthy
Abu Hatim ibn Hibban al-Busti: He was a Faqih and an author.
Ahmad ibn Hanbal: Trustworthy, and he is above al-'Ala' ibn Abd al-Rahman, above Suhayl ibn Abi Salih, and above Muhammad ibn Amr
Ahmad ibn Shu'ayb al-Nasa'i: Trustworthy
Ahmad ibn Salih al-Jilli: Trustworthy
Ibn Abi Hatim al-Razi: Trustworthy, upright in hadith, Faqih, possessor of Sunnah, and he is among those whose narration constitutes evidence
Ibn Hajar al-'Asqalani: Flexible in hadith
Al-Dhahabi: The Imam, trustworthy, upright
Rabi'a ibn Abi Abd al-Rahman al-Ra'i: Not trustworthy, Ibn Hajar said: People did not pay attention to Rabi'a in that regard due to the enmity between them.
Zakariya ibn Yahya al-Saji: Trustworthy
Sufyan ibn 'Uyaynah: I said to Sufyan al-Thawri: 'You accompanied Abu al-Zunad.' He said: 'I did not see in Medina an Amir other than him.'
Shuba ibn al-Hajjaj: He called him the Amir al-Mu'minin (Commander of the Faithful) in hadith
Abd Rabbih ibn Sa'id al-Ansari: I saw Abu al-Zunad enter the mosque of the Prophet, peace and blessings be upon him, with followers like those with a Sultan. Among them: someone asking about an obligatory prayer, someone asking about the reckoning, someone asking about hadith, and someone asking about a difficult matter.
Ali ibn al-Madini: There was no one in Medina after the senior Tabi'een more knowledgeable than Ibn Shihab, Yahya ibn Sa'id al-Ansari, Abu al-Zunad, and Bakir ibn Abdullah ibn al-Ash'aj
Malik ibn Anas: He does not approve of Abu al-Zunad, for he continued to work for the Banu Umayya until he died.
Muhammad ibn Isma'il al-Bukhari: The most authentic chains of narration of Abu Hurairah are through Abu al-Zunad from al-A'raj from Abu Hurairah
Muhammad ibn Jarir al-Tabari: Trustworthy
Muhammad ibn Sa'd, scribe of al-Waqidi: Trustworthy, prolific in hadith
Mus'ab ibn Abdullah al-Zubayri: Faqih of the people of Medina
Yahya ibn Ma'in: Trustworthy, an authority