The model for we Christians living in "Babylon" as the NT writers put it comes out of the experience of the exilic community in the OT. How should we relate to the culture around us? Few say it better than Tim Keller...
"It will not be enough for Christians to form a culture that runs counter to the values of the broader culture. Christians should be a community radically committed to the good of the city as a whole. We must move out to sacrificially serve the good of the whole human community, especially the poor. Revelation 21-22 makes it clear that the ultimate purpose of redemption is not to escape the material world, but to renew it. God's purpose is not only saving individuals, but also inaugurating a new world based on justice, peace, and love, not power, strife, and selfishness.
So Christians work for the peace, security, justice, and prosperity of their city and their neighbors, loving them in word and in deed, whether they believe what we do or not. In Jeremiah 29:7, Israel's exiles were called not just to live in the city, but also to love it and work for its shalom—its economic, social, and spiritual flourishing. The citizens of God's city are the best possible citizens of their earthly cities.
This is the only kind of cultural engagement that will not corrupt us and conform us to the world's pattern of life. If Christians go to urban centers simply to acquire power, they will never achieve cultural influence and change that is deep, lasting, and embraced by the broader society. We must live in the city to serve all the peoples in it, not just our own tribe. We must lose our power to find our (true) power. Christianity will not be attractive enough to win influence except through sacrificial service to all people, regardless of their beliefs.
This strategy (if we must call it that) will work. In every culture, some Christian conduct will be offensive and attacked, but some will be moving and attractive to outsiders. "Though they accuse you … they may see your good deeds and glorify God" (1 Peter 2:12, see also Matt. 5:16). In the Middle East, a Christian sexual ethic makes sense, but not "turn the other cheek." In secular New York City, the Christian teaching on forgiveness and reconciliation is welcome, but our sexual ethics seem horribly regressive. Every non-Christian culture has enough common grace to recognize some of the work of God in the world and to be attracted to it, even while Christianity in other ways will offend the prevailing culture.
So we must neither just denounce the culture nor adopt it. We must sacrificially serve the common good, expecting to be constantly misunderstood and sometimes attacked. We must walk in the steps of the one who laid down his life for his opponents."
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