In the episode “Face-Off,” in reference to A Mighty Fortress Is Our God.
ZACK (singing): A mighty fortress is our God, a bulwark never failing. (stops singing) Dude, what’s a bulwark?
BRIAN: What?
ZACK: It says, “A bulwark never failing.”
BRIAN: I think it’s a wall.
ZACK: Then why don’t they just say that? Bulwark sounds totally gay.
BRIAN: I don’t think you’re supposed to call a hymn gay. It’s like a sin or something.
ZACK: Whatever, man. I’m not saying bulwark.
Zack and Brian are rehearsing hymns in Rory’s garage to play for Mrs. Kim. They begin to play “A Mighty Fortress Is Our God.” When Zack sings a line about a “bulwark never failing,” he goes nuts and claims such a word is gay. Brian chips in that calling a sin gay is a huge sin, and so on.
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