Summary
Derek Prince wrote They Shall Expel Demons out of decades of firsthand ministry experience, and the book reads less like a theological treatise and more like a seasoned guide handing you a field manual. His central argument is disarmingly simple: casting out demons is not a fringe practice reserved for specialists. It is a basic function of the church that Jesus entrusted to every believer. If you follow Christ, deliverance is part of your inheritance and your assignment.
Prince opens with his own story, which is one of the most compelling parts of the book. He was a Cambridge-educated philosopher and a British Army veteran who came to faith in a barracks room during World War II. He did not grow up in a charismatic environment. He did not seek out deliverance ministry. Instead, it came to him through practical need. Early in his pastoral ministry, he encountered people who were tormented by forces that could not be explained by psychology or medicine alone. Rather than retreat into theological abstraction, Prince opened his Bible and began to follow what he found there. His transparency about his own learning curve gives the book a credibility that more polished treatments sometimes lack.
The Biblical Foundation
The first major section of the book lays out the scriptural case for deliverance. Prince walks through the Gospels methodically, showing that Jesus spent a significant portion of His public ministry casting out demons. It was not peripheral. It was not occasional. It was central to His mission. Prince points out that when Jesus sent out His disciples, He gave them authority over unclean spirits before He gave them instructions about preaching. The implication is that deliverance was not an afterthought but a frontline tool of the Kingdom.
Prince also addresses the book of Acts and the epistles, showing that the early church continued the practice of deliverance well beyond the earthly ministry of Jesus. He argues that nowhere in Scripture is there any indication that this ministry was intended to cease. The Great Commission, as recorded in the Gospel of Mark, explicitly includes casting out demons as one of the signs that would follow believers. Prince makes the case that the church did not outgrow deliverance; it simply forgot about it.
How Demons Gain Entry
One of the most practically useful sections of the book deals with how demons gain access to a person's life. Prince identifies several common entry points. These include involvement in the occult (even seemingly harmless activities like horoscopes, Ouija boards, and certain forms of meditation), unconfessed and habitual sin, emotional trauma and unforgiveness, generational patterns passed down through family lines, and exposure to certain types of false religion.
Prince is careful here. He does not adopt a sensationalist approach that sees a demon behind every problem. But he does argue that many Christians are unnecessarily suffering because they have not recognized the spiritual dimension of their struggle. A person might be dealing with persistent depression, irrational fear, compulsive behavior, or recurring illness that has a demonic root. Prince suggests that when natural remedies and good counsel have not brought relief, it is worth asking whether a spiritual factor is at work.
He also discusses the controversial question of whether Christians can have demons. His position is nuanced. He distinguishes between possession (ownership) and demonization (influence or habitation). Prince argues that while a born-again believer cannot be owned by a demon, a Christian can certainly be oppressed, harassed, or afflicted by demonic spirits that have gained entry through specific doors. He finds support for this in both Scripture and extensive personal experience. This distinction is important because it removes the stigma that has prevented many believers from seeking the help they need.
Recognizing Demonic Activity
Prince provides a practical framework for discerning when demonic activity may be present. He lists a number of indicators, including persistent emotional disturbances that do not respond to normal intervention, compulsive behaviors that a person cannot seem to break, chronic physical ailments without clear medical cause, recurring patterns of failure or self-sabotage, intense resistance to prayer or Scripture reading, and unusual reactions during worship or ministry times.
He emphasizes that discernment is a skill that develops over time and through practice. It requires sensitivity to the Holy Spirit, familiarity with Scripture, and a willingness to engage with the messy realities of people's lives. Prince warns against both extremes: the tendency to ignore the demonic altogether and the tendency to blame everything on demons.
The Process of Deliverance
The heart of the book is Prince's practical guide to conducting deliverance. He outlines a step-by-step process that is accessible to ordinary believers, not just trained ministers. The process generally involves several phases.
First, the person seeking deliverance needs to have a genuine relationship with Christ. Deliverance without salvation is like cleaning a house and leaving the door wide open. Jesus Himself warned about this in His teaching about the unclean spirit that returns with seven others.
Second, the person should confess and renounce any known sin, occult involvement, or ungodly soul ties. This is not about perfection but about honest repentance and a willingness to turn from whatever has given the enemy legal ground.
Third, forgiveness is essential. Prince identifies unforgiveness as one of the most common barriers to deliverance. Jesus was explicit that those who refuse to forgive will find themselves handed over to tormentors. Prince takes this literally and has seen countless cases where deliverance could not proceed until the person released bitterness and offense.
Fourth, the minister (or the person themselves) commands the demons to leave in the name of Jesus. Prince is straightforward about this. It does not require elaborate rituals or special formulas. The authority comes from Christ, and it is exercised through simple, direct commands of faith. He provides examples of how to address specific spirits by name or function, such as spirits of fear, rejection, lust, or infirmity.
Fifth, the person should be filled with the Holy Spirit and grounded in Scripture and community. Deliverance creates an opening that needs to be filled with the things of God. Without ongoing spiritual growth, the person is vulnerable to re-entry.
Maintaining Freedom
Prince devotes significant attention to what happens after deliverance. He has seen too many people experience genuine freedom only to lose it because they did not understand how to maintain it. His counsel is practical: stay in the Word, stay in community, stay in prayer, walk in obedience, and do not open old doors. He also recommends that people who have been delivered make a practice of actively resisting the enemy when old symptoms resurface. The initial deliverance may be dramatic, but the ongoing walk of freedom is a daily discipline.
Common Questions and Objections
The final sections of the book address the questions that Prince has been asked most frequently over the years. Can a Christian have a demon? (Yes, in the sense of demonization, not ownership.) Can deliverance happen without a minister present? (Yes, self-deliverance is biblical and Prince provides guidance for it.) What about mental illness? (Some cases have a demonic component, but Prince does not dismiss medical care. He advocates a both/and approach.) Is deliverance a one-time event? (Sometimes, but often it is a process that unfolds over time.)
Prince also addresses the fear factor. Many believers are hesitant to engage with deliverance because they are afraid of the demonic. Prince counters this directly: believers have been given authority over the enemy. Fear is itself a weapon of the enemy, and stepping into deliverance ministry requires stepping past that fear with confidence in Christ's finished work.
Why This Book Matters for Leaders
For Christian leaders, especially those in pastoral ministry, counseling, or inner healing work, this book fills a critical gap. Many seminary programs offer no training in deliverance. Many churches have no framework for it. As a result, leaders encounter people in genuine spiritual bondage and have no tools to help them. Prince provides those tools in a way that is biblically grounded, experientially tested, and practically accessible. Whether you are a senior pastor, a small group leader, or a lay minister, this book equips you to move in an area of ministry that Jesus clearly intended for His church.