An interesting book, but I don't think it can be fully understood by someone not familiar with the languages discussed. It seems to have been cited by Terrance McKenna, which gives me pause. If you assume McKenna is a disinformation agent, he is either building on disinformation or trying to muddy the waters of relevant information.
The book does, however indirectly, attack the idea that many of the religious figures of the past were simply literary tools to convey a particular message. Seeing the current level of debasement western civilization has fallen to with the rejection of religion it would not surprise me to find out that this is another rung on the ladder toward the narcissistic, dare I say Luciferian, world we have constructed.
It can also be seen as an early attempt to uncover (or promote) the use of the mushroom as a social control mechanism inside the mystery schools. This line of thinking can take you to the current day with psychedelics being more and more accepted as a treatment to mental illness (e.g. micro-dosing).
Again, if nothing else this is a wonderful book that is a feast for thought.