There are problems in the religious world that are hard to understand. The major solution is that the higher one goes on the scale of numinous value, the easier it is to fall from positive value to negative value. That is -if you take the scale of values to be increasing from pure form [the vessel] with no content to infinite God with no form, then you can see that for every true positive value, there are many negative values. The Sitra Achra. 

But in areas of all form no content -Logic-the fall from the true is not evil, but simply mistakes. But as ne goes into areas of greater content, the mistakes become the Dark Side.  

So you can see how the religious world (outside of the straight and narrow of authentic Torah--the Gra), becomes fanaticism for he Dark Side.

See the Friesian School approach.