John Piper has an excellent message on the perpetual question of living "in but not of" the world. A quick exerpt:

Romans 12:1-2

I appeal to you therefore, brothers,by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. ² Do not be conformed to this world,but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect.

Oh, how many questions this verse—Romans 12:2—raises that need thoughtful, biblical answers. For example, How does the command not to be conformed to this world relate to Paul’s statement in 1 Corinthians 9:22, “I have become all things to all people, that by all means I might save some”? How is becoming all things to all people not conforming to the world? Or how does the command not to conform to the world, that is, to be counter-cultural, relate to Paul’s words in 1 Corinthians 10:32-33? “Give no offense to Jews or to Greeks or to the church of God, just as I try to please everyone in everything I do, not seeking my own advantage, but that of many, that they may be saved.” How does not being conformed to the world fit with not giving offense to the world? You can’t always do both. How does not being conformed to the world fit with pleasing everyone for the sake of salvation? You can’t always please people if you refuse to conform to some of their thoughts and ways.

So the questions are many, and we will tackle some of them. My aim today is to give you a way to think about these questions. To give you some categories that I pray will be part of the renewing of your mind so that you can prove and embrace the will of God.

The reason there are questions like these is not because Paul slipped up and got confused about what it means to follow Christ in a fallen world. Paul was not confused. He was holding two Christian impulses—two principles—in balance. When Christ came into the world, and lived and died and rose from the dead, and set the redeeming kingdom of God in motion, and unleashed the mighty gospel on the world—two powerful impulses, or forces, spread everywhere the gospel spread.

The Indigenous Principle and the Pilgrim Principle
These two impulses are always in tension with each other. At times they push in opposite directions, and the great challenge is to find the biblical balance. Andrew Walls, in his book, The Missionary Movement In Christian History, calls these two impulses the Indigenous Principle and the Pilgrim Principle (Mary Knoll, N.Y.: Orbis Books, 2001, pp. 7-9). In other words, the gospel can and must become indigenous in every (fallen!) culture in the world. It can and must find a home in the culture. It must fit in. That’s the indigenous impulse. But at the same time, and just as powerful, the gospel produces a pilgrim mindset. It loosens people from their culture. It criticizes and corrects culture. It turns people into pilgrims and aliens and exiles in their own culture. When Paul says, “Do not conformed to this world,” and “I became all things to all people,” he is not confused; he is calling for a critical balance of two crucial biblical impulses. continue reading

John Piper - Do not be Conformed to This World - The Indigenous and Pilgrim Principle of Christian Living

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