Real, Knowledgeable, and Inner Teachers
Real: The second danger involves who one chooses to learn Kabbalah from. Even if a person is willing to live according to the Torah as part of the study of Kabbalah, he or she may nonetheless be receiving wisdom from an inauthentic source.
Let us give some examples of false sources. If you go to see some so-called kabbalist and he starts performing all kinds of calculations on your name (and your spouse’s name) and his conclusion is that either your name is no good and has to be changed, or you are not a good match for your spouse, then you can be a hundred-percent certain that this person is a charlatan. You would do best to keep as far away as possible from someone like this. The Arizal impressed upon us that in our generations there is no longer any need for, or legitimacy in using practical Kabbalah.
Knowledgeable: Secondly, there are many teachers who though they may mean well, are actually ignorant when it comes to the rest of the Torah. Because their knowledge of the revealed part of the Torah is so lacking, they cannot possible fully understand its concealed facets; consequently, whether consciously or unconsciously, they teach incorrect knowledge.
Inner: Finally, an even more subtle flaw regarding the source of one’s learning is that many of the teachers teaching today only understand the external aspects of Kabbalah. The largest part of the Arizal’s teachings is based on the distinction between external and internal aspects of things.7 Even someone who knows the Torah and knows Kabbalah, may be wholly lacking an inner understanding of them. Inner understanding refers to being able to not only intellectually understand the meaning of the teachings of Kabbalah, but rather, as explained in length in Chassidut, to be able to experience them in a rectified and holy manner. An authentic teacher of Kabbalah understands and relays to his students that Kabbalah is not referring solely to external reality. Recognizing a teacher who understands the wisdom of Kabbalah in an inner manner is dependent on the student’s sensitivity to truth.
The previous Lubavitcher Rebbe, Rabbi Yosef Yitzchak, said something very important in this respect. If a person gets used to looking at the world externally, it ruins his or her ability to later acquire an inner point-of-view or perspective. It is as though the external perspective does some kind of mental or spiritual damage to the Divine soul.
To explain this flaw a bit more, we may use the statement of the sages that a woman forms a bond only with the first man who makes her into a vessel (i.e., that she is intimate with).8 A teacher of the Torah is called a Rav. A teacher of the inner dimension of the Torah is called a Rebbe (with an additional Hebrew letter yud, at the end). The relationship between a student and a teacher of Kabbalah is like that between a wife and her husband. Thus, like a woman, you create a bond or intellectual covenant with the first teacher who inspires you with the teachings of Kabbalah. It is hard to break this bond—not entirely impossible, but very difficult.
...from Inner.org, the writings of Rabbi Ginsburgh (hassidic kabbalist in Israel).