According to biblical sources, an invisible war is taking place in our universe. This battle happening in the unseen realm is manifested in the physical realm (Eph 6:12-18). Our world is a battleground filled with good and evil spirits at war with one another. Since the beginning of time, this spiritual war has affected the human experience (Gen 3:1-19). However, there is a spiritual remedy for this problem: the gospel. Warfare preaching is saving lives trapped in our cosmic battle (Rom 1:16). The thesis statement of the Book is: "The proclamation of the gospel is effective against spiritual...