Sepher Yetzirah: The Book of Creation

The Sepher Yetzirah is one of the main and most important works of Kabbalah. Referenced by other works such as the Bahir, it is broken apart into a series of statements on the Hebrew alphabet and numeric systems. Among other concepts it expounds the concept of creation via the three mothers; Alef, Mem, and Shin, and their relative powers. It is one of the most integral works from which such types of occultism stem.