While working on my forthcoming book Unfashionable: Making a Difference in the World by being Different , I had a conversation about fundamentalism with a woman in her sixties. With tears in her eyes, she told me about her strict, cold Christian upbringing, which taught her that being different meant girls couldn’t wear pants, makeup, or jewelry, and guys had to have short hair and be clean-shaven. Guys and girls couldn’t swim together in the same pool; movies were strictly off-limits; alcohol was forbidden; and any music other than classical music and hymns was clearly “of the devil.” And associating with anyone who broke those rules was a violation of Christian purity.

This woman grew up being told that the church was a tribe, not a mission, and its chief objective was self-preservation from the world, not self-sacrifice for the world. When I explained that this wasn’t the kind of “difference” I was calling for in my book, she was understandably relieved.

The kind of self-righteous and radical withdrawal by Christians this woman described to me isn’t nearly as prevalent today as it was in past decades. That’s a good thing. But a less obvious form of cultural withdrawal and retreat is gaining momentum.

As I travel to churches around this country, I’ve noticed a growing trend: traditional places of worship are turning into sprawling campuses—cities within cities. Many churches now have their own restaurants, nightclubs, gymnasiums, bookstores, food courts, cafés, fitness centers, game rooms, and baseball fields. They provide their own sports leagues, exercise programs, and yellow pages. I understand the benefit of some of these things, but when churches provide a substitute activity site for everything under the sun—effectively setting up a parallel universe—we run the risk of abandoning contact with the very world God has commanded us and equipped us to change.

As Andy Crouch points out in his book Culture Making , “When we copy culture within our own private enclaves, the culture at large remains unchanged.” Christians who retreat into a comfortable subculture are bad missionaries—it’s that simple.

Remember, making contact is a key to salt’s and light’s effectiveness. That’s why Jesus’ command in Matthew 28:19 is that we “go.”

His command reflects the impact of the new covenant on the mission of God’s people. Under the old covenant, Israel was a nation blessed by God in order to be a blessing to other nations (Psalm 67), but Israel’s function as a community of blessing was primarily (though not exclusively) centripetal; instead of Israel going to the nations to give blessing, the nations came to Israel to receive it. Think of the Gentile women Rahab and Ruth, both of whom received the blessing of God by coming into his covenant community.

Under the new covenant, while it’s true that blessings await those who enter into the visible church, the church’s function as a community of blessing is primarily (though not exclusively) centrifugal; the church goes out into the world to bring God’s blessing of redemption and renewal to the whole earth.

My friend Trevin often makes the distinction between “sink Christians” and “faucet Christians.” Sink Christians, he says, view salvation as something to soak up. It fills the sink and they soak in the benefits (heaven, peace, Jesus, etc.). Faucet Christians see salvation as something that comes to them in order to flow out through them to the rest of the world as a blessing to others, as a pipe carries water from its source to a parched land. I like that.

We’re called to be “fishers of men” (Matthew 4:19), and we’re to be Christ’s witnesses “in Jerusalem and in all Judea and Samaria, and to the end of the earth” (Acts 1:8). We go out in order to give.

When we operate according to the idea “If we build it, they will come,” we fail to take into account this distinct nature of new covenant ministry and mission. Instead we’re called to operate with this mindset: “God is building; therefore we should go.”

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