[1] Ibn al-Banna kept a diary during his lifetime, part of which survives today and is valuable as a primary source about life in 11th-century Baghdad.
[1] Abu Ali ibn al-Banna was born in 1005 (396 AH); his family background is unknown.
[1] Ibn al-Banna started teaching while his own teacher, Qadi Abu Ya'la, was still alive.
[1] Some variants of the Muntazam say he wrote 500 books, but this appears to have been a scribal error; this then got repeated in other later biographies of Ibn al-Banna.
[1] He wrote about a wide range of topics, including ethics, theology, hadith studies, fiqh, sermons, history and biography, philology, pedagogy, and dream interpretation.
[1] The part that survives today eventually ended up in the possession of Diya ad-Din al-Maqdisi, a hadith scholar who had studied under Ibn al-Jawzi.
[1] As evidence of its private nature, it documents the internal dissension within the Hanbali community that he would not have wanted to reveal to the general public (particularly the controversial case surrounding Ibn Aqil), and it also contains unflattering information about Sharif Abu Ja'far, who Ibn al-Banna held in extremely high regard.
[1] Most likely, Ibn al-Banna used the diary as a personal notebook for writing down anything he thought was important or interesting, and then later selectively draw upon those notes for material he did intend to publish.
[1] Its private nature makes the diary a more reliable source for the events it covers and also "reveals the temperament of the author, his personality, his prejudices, more vividly and more accurately than the stereotyped accounts given in the biographical devoted to him.