The holy books of Thelema form the basis of the spiritual tradition laid down by the great mystic and magician of the 20th century Aleister Crowley. Their role in Thelema is as great as that of the Bible in Christianity or the Quran in Islam. Followers of the tradition believe that they were not created by the genius and intellect of Aleister Crowley, but were recorded by him on inspiration from above and through contact with higher beings.