Kabbalists made certain demands and restrictions for those who wanted to study Kabbalah. It is better to remain on the mechanical level of observing the commandments (the common Surrounding Light shines upon man and purifies him slowly) than to study Kabbalah alone. Unfortunately, we see self-taught Kabbalists and to what it has led them; they fabricate their own concepts about the spiritual world, populate it with all kinds of bodies, forces and their interactions, with winged angels, devils, witches, hell, and paradise, etc. They do this without understanding that the spiritual world is only inside of man’s soul, while only the Creator is outside. The Kabbalists were deeply concerned about all this. The principal commandment is not to make an idol out of your own egoism. Whether you want it or not, you worship it anyway – it is an idol made inside of you; from your birth, you worship only your own desires, thinking only about how to satisfy them. Not to make an idol means not putting your own idol in place of the Creator. If you truly desire to enter spirituality, to have any contact with it, do not make a false picture of it in your imagination, for it leads astray.

Courtesy of http://www.youtube.com/watch?v=ee9oFqxDDnU