The practice of Kabbalah has been going through something of a rewake in recent years, and with celebrities such as Madonna talking publicly about its benefits many people have become interested in the subject. At the same time as gaining in popularity modern Kabbalah has also evolved from its ancient origins so that what is called ‘modern Kabbalah’ is something quite different from the traditional subject. The origins of Kabbalah lie in early Jewish mysticism, but from those beginnings the study of Kabbalah has grown and branched out, first into a Christian and Islamic Kabbalah, and then further, so that today many people who study and practice this mystical and magical discipline do so outside of any particular religious affiliations, treating it as an independent spiritual system in itself. In many ways Kabbalistic teachings can be thought of as the essence of spiritual teachings. Kabbalistic principles can be used to understand and draw upon the teachings of a wide range of very different spiritual traditions by stripping away everything but the perfect ‘essence’ or soul of the teaching. The nature of Kabbalah means that rather than being composed of a set of rules, or rituals, and being essentially social and collective in nature, it guides its practitioners on a very personal journey and is composed in a large part of techniques; the path of Kabbalah is that of mysticism and magic. The entirety of Kabbalistic wisdom is contained within and expressed by a system of classification called the Tree of Life; it has 10 spheres, and 22 paths connecting them. The 10 Spheres can be thought of as describing objective existence whereas the 22 paths describe the subjective experience of being human. In addition to being used philosophically as a system of classification the tree of life is also used in meditative and ritual practices. Associated with each sphere and path are the Archangels and choruses of Angels, and other symbolic representation of their nature. The perfect example of this is invocation, in which the practitioners invoke the power of some spiritual force within themselves. This is described as a supernatural occurrence, but can be explained entirely as a psychological process harnessing the power of the subconscious mind. The Tree of Life can also be divided into three vertical pillars. All of the spheres belong to one of these three pillars and share particular characteristics with the other pillars which belong to that Pillar. The three pillars are called: The Pillar of Severity, The Pillar of Mercy and The Pillar of Balance.
Obviously this has just the tip of the iceberg of kabbalah, and if you are interested in this then I would buy a book on this subject.