He said: I heard Hashid ibn Ismaʿil relate, “I heard Ishaq ibn Rahwayh say, ‘Write down hadith from this young man—meaning al-Bukhari. Had he lived in the era of al-Hasan, people would still have needed him for his knowledge of hadith and his understanding of jurisprudence.’” (1)

He also said: I heard ʿAli ibn Hujr remark, “Khurasan has produced three men: Abu Zurʿah, Muhammad ibn Ismaʿil, and ʿAbd Allah ibn ʿAbd al-Rahman al-Darimi; and, in my estimation, Muhammad is the sharpest-sighted, the most knowledgeable, and the most deeply versed in jurisprudence of them all.” (2)

He said: I brought ʿAli ibn Hujr a copy of Abu ʿAbd Allah’s book. After reading it he asked, “How is that champion doing?” I replied, “He is well.” He said, “I know of no one like him.”

Ahmad ibn al-Dawʾ said: I heard Abu Bakr ibn Abi Shaybah and Muhammad ibn ʿAbd Allah ibn Numayr say, “We have never seen the like of Muhammad ibn Ismaʿil.” (3)

ʿAbd Allah ibn Ahmad ibn Hanbal reports: I heard my father say, “Khurasan has never produced anyone comparable to Muhammad ibn Ismaʿil.” (4)

Muhammad ibn Ibrahim al-Bushanji said: I heard Bundar—Muhammad ibn Bashshar—in the year 228 AH declare, “No one the equal of Muhammad ibn Ismaʿil has ever come to us.” (5)