Everyone needs to read this book. This is the story of a satanic worshipper who became a child of God. Readers realize that no human is too far gone, and that the love of God knows no bounds and turns no one away--regardless of how bad they've been. However, what I daresay is of more importance is understanding real spiritual warfare.
I am glad Leehan is now a slave of Yeshua Messiah, but some of what he did in his possession is worth noting for us to learn from. He would purposely go to churches to start conflict; he would memorize Bible verses and try to mess people up with them; he would go to singles groups and look for venerable women to satisfy his lust; he would purposely try to break up marriages; he would burn pages of the Bible; he would go after those who seemed young both in age and in the faith; he would see spirits; he would hear demons; he communicated with the spiritual realm; he saw / felt hedges of protection around certain people; he could tell in Bible studies who was really seeking God and who was immature in faith; and the list goes on.
What is most striking is that the forces of darkness can indeed enter "Christian circles" and pretend to be Christian to manipulate others. I'm not saying one has to be calling every single sinful person possessed, but I do think us as Christians need to be more on our toes (Matt 10:16). Things like blood sacrifice, spiritual influence, voices, and so much more are told with horrifying clarity. The book even includes eye-witness accounts from people who back up Leehan's story.
Both before and after his conversion, Leehan comments about how little Christians know about the God they profess. Christians, please read your Bible and get to know your God. Church and devotionals are great, but God is bigger than the beatitudes and self-help lessons. Read a translation you understand and get to know what you are dealing with. Reading this book was hard, and when Leehan wrote of what God told Him, I started to cry. Some words on pg 211 include: "I created you. I chose you first. I will never leave you. You will never leave Me. You are in My hands; you are in My arms."
While I have not been as in deep or intensely lost as Leehan, I can identify with a lot of what he went through in terms of possession, the dark side, spirits, blood rituals, and more. Like Leehan, the love of Christ grabbed me by the collar and did not let go (look at Job 30:18 and verses around it). The forces of darkness are real, and don't you dare think for one moment that you don't have to understand them. I'm not saying to go read every occult book or obsess with all that research; the Bible has enough in it (2 Tim 2:15).
I personally feel a hedge of protection around me as I claim Zech 2:5 for the fire of glory around me. I heard God whisper He loves me (Rom 5:5) as I am flooded with God (Eph 3:19). Every day is a battle (Eph 6:12) but I stare at God (Heb 12:2). God protects His own, yes, but from the Book of Job, we see that God allows even the upright to be tested. It is my sincere hope that you will never have to see, hear, or come into contact with the dark forces of this world. However, I assure you they are real.