Our culture is fascinated with demonic possession. Movies like The Exorcist and Paranormal Activity make it seem like the greatest spiritual danger is to be taken over by an unclean spirit. Thanks to pop culture, we imagine dramatic exorcisms, screaming voices, and supernatural chaos.

But in Luke 11, Jesus does not primarily warn about possession; in fact, exorcising the demon is hardly mentioned at all. 

Instead, He warns about what happens after a demon is cast out. He tells us that the real danger is an empty house—because an empty house is a vulnerable house.