John Granger said this quote

“ Second, the reason to embrace and celebrate these novels as the countercultural event that they are is due largely to the subliminal messages delivered by Harry and friends in their stolen wheelbarrows. Readers walk away, maybe a little softer on the occult than they were, but with story-embedded messages: the importance of a pure soul; love's power even over death; about sacrifice and loyalty; a host of images and shadows about Christ and how essential 'right belief' is for personal transformation and victory over internal and external evils. ”