Is it possible to know the truth about Jesus Christ, to understand who He was and what He did, and yet not have a genuine faith in Him, just a head knowledge? Is it possible to go through some motions—bow your head, pray a prayer, walk an aisle or some other rituals, but never exercise real faith?
James was writing to converted Jews who knew a lot about ceremonies and rituals and going through the motions. They were good church people. And yet as a pastor, he was concerned that their faith was dead.
And so to make his point, he introduces a shocking comparison. Worse than comparing them to ducks, he compares them to demons.
James shows us the insufficiency of dead faith through the case study of demons.