Al-Ḥasan ibn ʿĪsā reported: Sakh r— a close friend of Ibn al-Mubārak—told me:
“We were young boys in the Qurʾānic school. Ibn al-Mubārak and I passed by while a man was delivering a sermon—an unusually long sermon. When the preacher finished, Ibn al-Mubārak said to me, ‘I have memorised it.’
A man standing nearby overheard and said, ‘Recite it.’ So he repeated the sermon word for word, having retained it all.” ⦗1⦘

Nuʿaym ibn Ḥammād said: I heard Ibn al-Mubārak say, “My father once told me, ‘If I find your notebooks, I will burn them!’ I replied, ‘That will not harm me in the least, for they are already here—in my breast.’” ⦗2⦘

Abū Wahb Muḥammad ibn Muzāḥim remarked, “How astonishing it is that a man hears a hadith from Ibn al-Mubārak, traced through a certain transmitter, yet still feels the need to seek out that very transmitter so that he may hear it from him directly!” ⦗3⦘

Ibn Khirāsh said, “Ibn al-Mubārak was a native of Marw; he was reliable (thiqa).”

Al-Qāsim ibn Muḥammad ibn ʿAbbād related: I heard Suwayd ibn Saʿīd say, “I saw Ibn al-Mubārak in Mecca. He came to the Zamzam well, drew some water, then faced the qiblah and said, ‘O Allah, Ibn Abī al-Mawwal has narrated to us, on the authority of Muḥammad ibn al-Munkadir, on the authority of Jābir, that the Prophet ﷺ said: “The water of Zamzam is for whatever it is drunk for.” I now drink it to quench the thirst of the Day of Resurrection.’ Then he drank.” ⦗4⦘