 Maimonides became Nagid, or leader of the Egyptian Jewish community in 1171, and as a follower of the Babylonian Talmud, was not a "member" of Ben Ezra.However, many of the geniza documents, including some in his own handwriting, discuss his life and work, and are the most important primary biographical sources for him.The style of the carving on the Torah ark door is incompatible with that of the Fatimid Caliphate (909–1171 CE), and is more representative of the Mamluk Sultanate (1250–1571 CE), specifically the 15th century.