Anyone looking for an encyclopaedia of occultism, or alternatively a lurid catalogue of debauchery, is likely to be disappointed by this. It's a long, rambling book which, far from telling you anything specific about magic, tends to debunk the phenomenon. Levi seems at this stage to have undergone something of a re-conversion to his childhood Catholicism, which he regards as the current and final inheritor of the esoteric tradition - or 'universal orthodoxy' as he calls it. Which would be an interesting thesis, except that he doesn't really attempt to substantiate this or any of the book's other assertions.
I found it a frustrating book to read. One chapter after another begins with striking insights into philosophy and spirituality - only to wander off into vagueness, symbolism and apocryphal gossip about people you've never heard of. Personally, I find A E Waite's introduction and commentary a useful framework and occasional corrective. It's hard to pin down exactly what Levi himself believes but - as Julian Cope once said - it's obviously pretty far out. And then, who is the rabbit he pulls out of the hat right at the end, as the supposed fulfilment of Christianity? Who but Napoleon?
If that doesn't mark him down as irredeemably cracked, read this as at least an interesting exercise in speculation and interpretation, from a very influential figure in the modern Revival of magic.