The Shack is a very interesting book. I am not only glad I read it, I am changed by reading it. It is a fictional book allowing it to penetrate into your psyche and catch you unguarded, raw, and vulnerable. It brought me to the basic principle Christianity revolves around - love. Only because of love. God loves us so we can love - love Him, love others, love ourselves. The book also allowed me to envision how that love could affect my life when realized through the lives of the characters. Only because of love.
When I heard of others reading the book, I would hear how they put the book down and then pick it up after a break. I understand because some of the realizations were so profound, I felt that if I rushed through reading it, without taking a few days or a week to absorb it, I would not have been ready for the next impacting divulgence of my heart.