If you read no other book about what we are learning about the other side, please make it this one. He has read the literature through and then participated in the best available training at the Monroe Institute. I found the work both complete and comprehensives as well in exploring his own reactions to all this.
The spirit body we all have is physically real but formed from second tier matter. Thus on death we return perceptionally to this second tier world and participate in eternal life there. The constructs there are formed by shared imagination although Paul does not make this distinction.
In the spirit world we all become Hobbits. My own Lucid Dream returned me to a cottage similar to the farm house of my youth to meet my mother. The affinity was there. Was Tolkien imagining the After Life?
Eyes of an Angel