I suspect that there is something even more terrifying than the terror and horror in the face of death of which Luther wrote. And that even greater terror is the Divine presence itself. If by some unlucky accident any of us were to find a purely individualistic path to the sacred, we would go mad. To make possible the existence of the universe God must with draw his presence and make room for it, what the Kabbalists call zimzum, or concentration; to allow us to approach the Creator of the Universe without burning up our own personality like a dust-speck in a blast furnace, God gives us specific means to approach him: the performance of sacrificial service (in post-Temple times, the prayer service) and the other mitzvot.

The sacred is awesome, and potentially terrifying. The Torah tells us to approach the sacred via the Mitzvot, which are not in heaven but given to us on earth. [Some people] do no-one a service by approaching it through the self-help section of the bookstores.