Like most people who haven’t listened to much Christian rock, I associate it primarily with smug power ballads about a loving God. But there is actually such a thing as Christian metalcore, and this Georgia band’s rep with the kids is at least as much about their sound as their relationship with Jesus. You could be forgiven for not realizing Norma Jean is a Christian band at all; the lyrics are usually incomprehensible, and even on the page they’re pretty ambiguous. On “Vertebraille,” from this year’s O God, the Aftermath (Tooth & Nail), when new singer Cory Brandan shrieks the refrain “It’s all your fault” it’s impossible to be sure whether he’s exploring some deep theological questions or just really, really mad at a girl. But metalcore records of all denominations are justified not by faith but by works–the heaviness of the guitars, the inhuman quality of the screaming, the extent and technical difficulty of the stop-start breakdowns–and O God scores high on all counts. Satisfyingly, chaotically loose rhythmic fits litter the songs, the dual guitar lines have inherited some Bleach-y string-bending sludge from the Cobain estate, and Brandan’s tattered screams really nail everything shut. He howls accusations into the maelstrom like Job must have when he found out the good Lord was playing him. As I Lay Dying headlines, Norma Jean plays third, and Madball and A Life Once Lost open. Sat 12/10, 6 PM, House of Blues, 329 N. Dearborn, 312-923-2000 or 312-559-1212, $15 in advance, $17.50 at the door. All ages.