There are many minhagim that are prevalent in the orthodox community that seem to have the status of halacha and are either based on Kabbalistic concerns or whose main objective is to protect from the Ayin Hara (Evil Eye). To what extent does the prohibition against being superstitious and modifying one’s behaviour based on superstion apply to or differ from these mihagim?
There is a general misunderstanding that associates Kabbala with superstition, and the many charlatans who call themselves Kabbalists and charge the unwary fortunes for false advice are to blame for it. True Kabbala is the understanding of the connection of G-d to Man and the universe- it is abstract, deep and meaningful. The “evil eye” is a concept mentioned in the gemara (for example Berachot 20a) and the Shulchan Aruch (Orach Chayyim 141, 6 as an example). It is understood as a natural human force involved in the fact that how others see them effects most, but not all, people (see HaRav Kook, Ein Aya Berachot 20a). Attempting to predict the future through magic, or deciding on the basis of omens on a course of action is strictly prohibited. The deciding rule is to keep the commandments incumbent upon us as delineated by the Shulchan Aruch and to place our faith in G-d regarding what is not in our hands. “Have a perfect faith with Hashem, your G-d” (Devarim 18,13; R'ma Orach Chayyim 664 1).