History of the Prophets and Kings

Abu Ja’far Muhammad ibn Jarir al-Tabari (839–923) compiled his history from the collections of earlier traditionists. He rarely speaks in his own voice. He gives each report under the year it belongs to, with the names of those who passed it on, and often gives several reports that do not agree.

For the surrender of Jerusalem he writes nearly three centuries after the event. The document he quotes as Umar’s letter to the people of the city is the full text of what is called the assurance or covenant of Umar. It may preserve the substance of real terms, but no copy from the seventh century exists to compare it with, and al-Tabari himself gives two different years for the conquest.