Azhar Book

The Azhar Book is a text in the fictional Dune universe created by Frank Herbert.

Appendix II: The Religion of Dune in the novel Dune refers to The Azhar Book as "that bibliographic marvel that preserves the great secrets of the most ancient faiths," and notes that it predates The Orange Catholic Bible, the key religious text of the Dune universe which "contains elements of most ancient religions.". The creation of The Azhar Book is also attributed to the Bene Gesserit.

The appendix subsequently quotes Paul "Muad'Dib" Atreides, and references his words back to ancient texts using, The Azhar Book:

In Dune, Lady Jessica examines the manual included in a Fremen desert survival kit on Arrakis:

The glowing tab of the Fremkit manual between them on the tent floor caught her eye. She lifted it, glanced at the flyleaf, reading: "Manual of 'The Friendly Desert,' the place full of life. Here are the ayat and burhan of Life. Believe, and al-Lat shall never burn you."
It reads like The Azhar Book, she thought, recalling her studies of the Great Secrets. Has a Manipulator of Religions been on Arrakis?

The Bene Gesserit practice "religious engineering" through a faction called the Missionaria Protectiva, which spreads contrived myths, prophecies and superstition on primitive worlds so that the Sisterhood may later exploit those regions. It is later confirmed that the Fremen religion has been thus influenced.

In Children of Dune, Leto II quotes from "the Bene Gesserit Azhar Book" when discussing with Ghanima their suspicions about their aunt Alia:

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