Al-Tayalisi said: Imran al-Qattan narrated to us, from Bakr ibn ʿAbd Allah, from Abu Rafiʿ, from Abu Hurayrah, who related that he once met Kaʿb and began recounting reports to him and asking him questions. Kaʿb remarked, “I have never seen anyone who has not read the Torah yet is more knowledgeable of what it contains than Abu Hurayrah.” (1)

Hammad ibn Shuʿayb narrated, from Ismaʿil ibn Ummayyah, from Muhammad ibn Qays ibn Makhramah:
A man came to Zayd ibn Thabit and asked him about a matter. Zayd replied, “Go to Abu Hurayrah, for while he, So-and-so, and I were in the mosque making supplication, the Messenger of Allah ﷺ came out, sat down, and said, ‘Return to what you were doing.’” Zayd continued: “So my companion and I supplicated, and the Messenger of Allah was saying āmīn. Then Abu Hurayrah supplicated, saying, ‘O Allah, I ask You for the same as they have asked You, and I ask You for knowledge that will never be forgotten.’ The Messenger of Allah ﷺ said, ‘Āmīn.’ We then said, ‘And we too ask Allah for knowledge that will never be forgotten.’ He said, ‘The man from Daws has outstripped you in that.’”

Al-Hakim included this narration in his Mustadrak. (2) Yet Hammad is weak.

Saʿid ibn ʿAbd al-ʿAziz narrated, from Ismaʿil ibn ʿUbayd Allah, from al-Saʾib ibn Yazid, that he heard ʿUmar say to Abu Hurayrah, “You must stop narrating hadith from the Messenger of Allah ﷺ …”