Are we really living in an era marked by an invasion of demons who hide behind illness, unemployment, celibacy, poverty and all our failures? What is really at stake in the instrumentalization of spiritual warfare and how can we understand the renewed interest in hunting down demons in Christian circles? These questions, which animate and feed religious contemporaneity, are at the heart of this book. In an analytical approach, the author reveals all one needs to know about Christian identity and the modern crisis of spiritual warfare. He demonstrates that spiritual warfare is simply the constant and renewed effort that every Christian makes to make himself available to the action of the Holy Spirit, in order to be of service to God. Through the reflections presented in this book, the modern crisis of spiritual warfare appears as a symptomatic phenomenon of deregulated societies that are experiencing the trauma of a poorly negotiated spiritual acculturation and the excessiveness of the claim to access a paganized religious modernity.