The Ancient Liturgy of Truth comes with Ultima III. It is 18 pages long. In-game, Alizarkanon, prophet of the Cult of Truth is the author of the book. In real-life, Margaret Ellen Weigers and Roe R. Adams have written the book.
The following topics are part of the book:
- The prophecy
- The spells of the Cleric
The book is written from an in-game perspective, and is presented as a manuscript given to the player by the Cult of Truth. Numerous full page illustrations accompany the spells, and it presents the intricate rituals required for casting clerical spells in the game.