The Lexicon

The Lexicon, also titled The Penultimate Treatise on Magic and its Splendor, is the written word by the God Azuth, this document includes details on the Weave itself, the basic foundations, rules, and principles. This god asks for no prayers, for simply using magic within what Azuth deigns to be respectful is devotion to Him.
The book also includes instructions on all spells that Azuth allows, though to the casual reader it will read mostly like nonsense.
The inclusion of the word Penultimate hints that there is another book to be released.