[8] He was one of the most learned and authoritative scholars of his time in all matters pertaining to the Arabic language, antiquities and stories, and is constantly cited by later authors and compilers.
Al-Jahiz held him to be the most learned scholar in all branches of human knowledge, and Ibn Hisham accepted his interpretation even of passages in the Qur'an.
[11] Hugh Chisholm disagrees, holding that Abu Ubaida was neither a Kharijite nor a racist but simply a supporter of Shu'ubiyya and opposed the idea that Arabs were inherently superior to other races.
In Chisolm's description, he delighted in showing that words, fables, customs, etc., which the Arabs believed to be peculiarly their own, were derived from the Persians.
Almost half of all information about Arabia before Islam reported by later authors was by way of Ma'mar, and he wrote the earliest extant Tafsir or commentary on the Qur'an, which was the basis for explaining any verses in the prophetic biography written by Ibn Hisham.