From a long article found here:
http://dir.salon.com/story/books/review/2005/07/01/promethea/index.html
"Apparently emboldened by the fact that his collaborators hadn't run away screaming, Moore threw the plot out the window for most of Books 3 and 4, and devoted them to an extended explanation of the Kabbala's Tree of Life, the map connecting the sephirot or spheres representing God's attributes (or states of mind) in the Jewish mystical tradition. (The links Moore suggests between the Kabbala and the Tarot are that the 22 major arcana correspond to the 22 paths between sephirot on the Tree of Life, and that, more important, both systems are useful as allegorical representations of the range of human experience.) The conceit of "Promethea's" middle act is that Sophie and her spirit guide, the previous incarnation of Promethea, spend a chapter apiece traveling through metaphorical representations of each of the 10 Kabbalistic sephirot (plus an extra "invisible sphere" Moore sneaks in between the third and fourth).
There's a lot of ungainly expository dialogue in those two books ("This is the fourth sphere, right? 'Chesed,' there on the arch above the Jupiter symbol. I think it means mercy"). Their ratio of profundity to claptrap varies with the reader's openness to semi-digested Crowley, and occasionally Moore threatens to sprain an eyelid from winking so hard. (Sophie meets Hermes, who tells her that gods, as "abstract essences," can only be perceived through linguistic constructs like "picture-stories." Picture-stories? she asks. "Oh, you know. Hieroglyphics. Vase paintings. Whatever did you think I meant?") Some readers complained at the time these installments first appeared that they felt like Moore was lecturing at them, and that's absolutely true. But complaining about "Promethea's" transformation from a graphic novel to a graphic textbook is missing the point: The idea of it isn't to tell a story so much as to present a gigantic mass of arcane philosophy as entertainingly and memorably as possible.
In fact, the Kabbala volumes of "Promethea" are thrilling, partly because they're total eye candy. Williams and Gray draw each chapter in a style of its own, with a color palette dominated by the part of the spectrum associated with that chapter's sphere. The panel backgrounds for the "Chesed" sphere are painted with blotchy, van Gogh-inspired brush strokes, suffused with blue; Binah, the realm of the whore Babalon, is drenched in blacks and dark, tinted grays, with outlines that crinkle like woodcut prints. The colors of the highest sphere, Kether, are traditionally white and gold, and its chapter is illustrated almost entirely in shimmering, pointillist golden yellow. When the story gets back to earth a few pages later, it's hard to readjust, although Williams keeps up the delirious compositional tricks from the Kabbala section."
"As entertaining as it is, most of Book 5 is an exercise in clearing the decks for the final chapter, and by then it's clear that hardcore formalist Moore has arranged the series into 32 chapters for a reason. The final one is 32 pages long, each page corresponding to one of the tarot's 22 major arcana or one of the 10 spheres of the Kabbala. (They can be read in the order printed in the book, or they can be assembled into two four-page-by-four-page arrays -- which form gigantic images of Promethea's face -- and read in that order instead.)"