Great book on the Holy Spirit. I like the use of images, ex.: "A piece of wood is thrown into the fire. The fire envelops, penetrates, and possesses it. To the wood, being possessed by the fire and burning are the same thing. But, at first, the wood is not wholly burned, because the fire has not penetrated it completely. Penetration and possession come about little by little as the wood burns, until, perfectly penetrated by the fire, it is converted into it and burns with the same fire and has all the characteristics of fire."