Barleywine
I think Crowley is more connecting Thoth Tarot to Greek Myths, Hinduism, Yoga and Buddihsm rather than Christianity in his Book of Thoth and all of his other writings too, hence the reason one has to establish own connecting system between Tree of Life and Thoth Deck, by studying Qabbalah and Tree of Life from other various sources, if one believes they are truly the system for them. I was more into connecting Tarot with Astrology, but now am trying to learn Qabbalah for the process.
Crowley makes a great deal of use of the Tree of Life in his treatment of the Minor Arcana and their relation to the sephiroth, what I call the "energy flow" model derived from the "descent of Spirit into Matter" (Ace through Ten).