Here's a riddle: A young man walks into a building. From the outside, it looks like a nondescript, run-down, abandoned warehouse. Inside he finds mood lighting, music with throbbing bass, and young people wearing skinny jeans and superfluous scarves. A bar off to the side offers drinks of some sort, and a frenetically lit stage is shrouded in fog. Jumbo screens display what appear to be music videos. Everywhere people text on their iPhones.

A young woman with a nose ring and a vaguely Middle Eastern tattoo comes up andintroduces herself. She makes awkward (but refreshingly earnest) small talk about her passion for community gardens and food co-ops. She asks him if he has heard Arcade Fire's new album, and compliments him on his bushy beard and lumberjack look. Beards like that are cool, she says. Eventually she asks him for his contact information.

Question: Is the man in a bar? Or is he in a church?

It could go either way.

Welcome to the world of hipster Christianity. It's a world where things like the Left Behind book and film series, Jesus fish bumper stickers, and door-to-door evangelism are relevant only as a source of irony or nostalgia. It's a world where Braveheart youth-pastor analogies are anathema, where everyone agrees that they wish Pat Robertson "weren't one of us" and shares a collective distaste for the art of Thomas Kinkade.

The latest incarnation of a decades-long collision of "cool" and "Christianity," hipster Christianity is in large part a rebellion against the very subculture that birthed it. It's a rebellion against old-school evangelicalism and its fuddy-duddy legalism, apathy about the arts, and pitiful lack of concern for social justice. It's also a rebellion against George W. Bush—style Christianity: ...

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