Ancient Iranian religion was strongly connected. Beginning in the early 10th-century BC, the ancient Iranian religion was gradually displaced by Zoroastrianism, which contains many essential aspects of its predecessor. The sources on ancient Iranian religion, though limited, consist of textual and material sources. The textual sources are both Iranian and non-Iranian. An important Iranian source is the Avesta, which are Zoroastrian sacred scriptures made in the Avestan. This is considered the principal source of knowledge on ancient Iranian religions. It is a collection of several texts that seems to have been over a large span of time by a variety of authors. These
The Book of the Book the "New York Review of Books", stating "Ignorance, I will admit, is no crime, and I am sure that Dr. Elwell-Sutton does not claim to be a literary man. But motivation has its mysteries." A review in Studies in Comparative Religion stated "The Book of the Book, which purports to be an object lesson in the problem of the container and the content, consists of some fifteen pages of print bound together with over 250 blank pages". The Book of the Book The Book of the Book is a book by Idries Shah. The majority of the book's 200 pages