Why does the demon that possesses Regan react to the “fake” holy water sprinkled by Father Karras?
BEST EXPLANATION: It’s hard to believe—as some have suggested—that the demon mistakes the tap water for water blessed by a priest. It certainly makes the entity that much less frightening.
It makes more sense to us that the demon—cunning and wicked—wants to sow some seeds of doubt in the mind of the young Jesuit priest, already burdened by a crushing crisis of faith.
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