Reader: Why do you take issue with parts of Kabbalah? Through Kabbalistic study, many great Rabbis were known to have deep insights into reality with ability to "see from one end of the world to the other."
Rabbi: I do not know your meaning of "seeing from one end of the world to the other." If an idea is true, it doesn't matter where it is found. If a notion is false, claiming "it forms part of Kabbala" cannot make it correct. 2+2=5 is false, regardless of the book in which it is written. When discussing written works other than God's word – which is where Zoharistic Kabbala falls as a fallible human creation – we must evaluate ideas based on their own principles.
Reader: Their [Kabbalistic Rabbis] prayers, time and time again were found to be potent. They did not credit themselves with magical powers but with the ability to pray more effectively, having learned it from their studies. They would rebuke others for not applying themselves to pray sufficiently, clarifying that anyone can achieve these levels of response. All we needed to do is understand Who we speak to and have an honest conversation with Hashem, understanding that He does hear us.
Rabbi: This idea does not originate with Kabbala. It's the basic premise of tefilah, "Know before Whom you stand." And God's response does not depend on one's study of Zoharistic Kabbala. Tanach is replete with examples.
Reader: These same Rabbis invariably studied Kabbala, be they Chassidim, Sefardim or any other sect. How do we reconcile these seeming contradictions: They trust a text [Kabbala] that is questionable, but it does appear to help them develop a closer relationship with Hashem.
Rabbi: One's "closer relationship with Hashem" is not something anyone can validate about another person. And it is arrogant and baseless for anyone to suggest he or she is now "closer to God." How does one know this? A tznua [modest person] which is what Moses was, would never make such a claim. God alone knows whether one person get's closer to Him. You will never find any Prophet of truly righteous person boast, nor boast about which he cannot know. And others cannot know if a given Rabbi is close or distant from God. Either way, such claims are baseless and contrary to Torah. Torah is complete, and we are not to add to, or subtract from it. Suggesting Zohar contains more than Tanach and Torah She B'al Peh, through which one gets closer to Hashem, is a wrong concept.
Whatever in Zohar is valid, meaning, what is synonymous with Torah, teaches us nothing new and it may be followed. Whatever in Zohar opposes Torah, must be rejected.
My view is that the ancient Rabbis who supported Kabbala did not have the same Kabbala that exists today that contains false and heretical ideas. Ibn Ezra spoke of Kabbala. There existed a body of transmission, which is what is meant by the word "kabbala." Nothing more. Once one projects mystical notions onto Zohar, Kabbalah and Torah, he no longer follows Torah.