That’s the knife-twist. The show never gives an easy answer. Episode 5, "Through My Most Grievous Fault."
Light a candle. Pour some wine. Say a Hail Mary. And give this unholy masterpiece your time. exorcist 2017
Without spoiling: a priest gives his last confession while possessed. The demon mimics his dead mother’s voice. The priest absolves himself . Then he walks into a furnace. That’s the knife-twist
You can find both seasons on Amazon Prime (in the US) or AMC+. exorcist 2017
The show earned its R-rating-on-TV moments (head-turning, spider-walking, pea-soup vomit), but the real horror happens at the dinner table. You don’t need CGI for that. Most exorcism media treats the Church as a prop. The Exorcist (2017) treats it as a battlefield.