Audience-Alienating Premise: A veryvisceral retelling of the religious text of Christianity, one of — if not the most — widely practiced religions in the world, that opens with God disemboweling Himself and ends with His Son being dismembered doesn't exactly scream "box office smash."
Memetic Mutation: The opening sequence of God disemboweling himself shows up a lot in "scary GIF" compilations.
Nausea Fuel: God defecates as he disembowels himself, which gives us the only sound effects in the movie that just makes the scene that much more gross.
Signature Scene: The opening scene of God disemboweling himself. Stills of that scene are the most commonly used to publicize the film.
Squick: It starts with God disemboweling himself and just gets worse from there.