Which is the highest rank among the titles of “Al-Hafiz,” “Shaykh al-Islam,” and “Amir al-Mu'minin fi al-Hadith” that are conferred upon past scholars, and who deserves these titles?

The scholars of Hadith terminology have differed on the exact meaning of the title "Al-Hafiz," yet they agree that it is exclusive to the people of Hadith. This title was used to describe scholars in the third and fourth centuries due to their extensive memorization, and their knowledge of defects (ilal), narrators (rijal), and texts (mutun). Later, people broadened its use to include anyone who knew more Hadith than they were ignorant of.

As for the title "Shaykh al-Islam," it is a great title bestowed upon someone who surpassed their peers in knowledge, piety, and service to Islam, in addition to being elderly. However, in later centuries, it became debased and was applied to those who did not deserve it.

As for the title "Amir al-Mu'minin fi al-Hadith" (Commander of the Believers in Hadith), it denotes someone who excels their peers in knowledge of Hadith. This title was not widely known except for a few select individuals.

Regarding which of these titles is the highest, it depends on the person being described. Whoever combined memorization, jurisprudence, good deeds, and old age deserves the title "Shaykh al-Islam," and it would be the highest at that point. The title "Amir al-Mu'minin fi al-Hadith" is higher than "Al-Hafiz" if it is truly merited.