In chapter 14 of Unfinished, Stearns directly discusses spiritual warfare that the church finds itself in, although he has been using the language throughout the whole book. He spends a bit of time discussing how we don’t always know what is going on behind-the-scenes in the spiritual realm, like the book of Job, and some other elements that a lot of mainstream Western Christians wouldn’t even consider because we tend to think of it as superstitious.
The most interesting part to me, though, and an analogy I’ll definitely use in the future, is comparing the cross to D-Day. Some wonder why, if Jesus defeated death and evil on the cross, there is still evil in the world. The cross is a now but not yet victory, much like D-Day. When the Allies established a Western front through the D-Day landing, victory was assured; I don’t think any historian would argue that Germany was doomed from then on as they spread their resources across two fronts and multiple attacking nations.
The cross was D-Day in God’s plan to rescue his children. It was the decisive battle in a great struggle and represented the defeat of Satan. And it, too, was costly.