What is a Church?

This morning Andrew Sullivan put up a quote by Gary Wills on why he stayed Roman Catholic:

“It’s our concrete experience of the local church that’s especially meaningful to us. There’s an interesting contrast between born Catholics and converts. Converts are often much more rule-directed. Catholicism isn’t something that they breathed in from their childhood, so they think that if you don’t toe the line on abstract doctrine you can’t be part of the Church. But to a born Catholic, Catholicism means their parish, their priest, their fellow worshippers. It’s all very concrete. Papal directives usually seem kind of abstract and unimportant compared to that lived experience.”

Now I know that for protestants there is no equivalent to papal decrees, but I do not think that the quote is without comparison. I grew up in the Presbyterian¬† church and I am sure that I unconsciously absorbed all kinds of vaguely Calvinist ideas, but church was hardly about doctrine and I certainly didn’t have a grasp on why Calvinism was better than this or that. Christians spill a lot of ink and server space on doctrine, but is that church, should it be church? I’m not saying that doctrine doesn’t matter, rather, how much should it matter?