ork the seminal holy book of his thelemic religion The Book of the Law, Liber AL vel Legis. New pocket edition measuring 4 x 6 inches. The book was allegedly received on 8 April, 9 April, and 10 April in Cairo in the 1904. Crowley attributed the authorship to an praeterhuman intelligence named Aiwass. Crowley would later identify the entity as his personal Holy Guardian Angel.