The Essential Kabbalah: the Heart of Jewish Mysticism

Plot

The door to this ancient and mystical sect of Judaism is opened and its wisdom and philosophies are revealed through its writings and the clear interpretations of the author.

This is the first book that I ever read on the Kabbalah and I would recommend it as the best starting place to anyone who is interested in the subject. The reason I recommend it over Major Trends in Jewish Mysticism (by Gershom Scholem, arguably the most important and influential scholar in this area) is because this book gets the reader directly in touch with the texts (and, thanks to the commentary, the meanings derived from them) that make up what has come to be known as "Kabbalah."
Matt divides his book into sections by topic and each entry contains an excerpt from a text that fits the particular topic. The introduction contains a brief essay on the development of the Kabbalah; in the back of the book is a commentary on each passage, helping the reader to understand aspects, meanings, and references in the texts that otherwise may have not been understood.