In calling the church to be separate, Paul made a surprising connection to the Old Testament: “Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed” (1 Cor. 5:7). Paul grounded his call to separateness in the story of Israel’s deliverance from Egypt. The Passover, together with the Feast of Unleavened Bread, celebrated Israel’s deliverance from death and their separation from the land of Egypt. Anything brought back among them from their former way of life was a threat to their separate status as God’s people. The church, like Israel, was called to “go out from their midst, and be separate from them” (2 Cor. 6:17). They were to come out of Egypt and never to let Egypt come back into them.
Paul recognized that the church in Corinth was confused over the issue of separation. They appear to have taken his call to be separate as unreasonable. Their questions probably went as follows: “What are we supposed to do, create our own little sectarian group with our own morals?” And what about our differences with other Christians? Many Christians today share this confusion.
Paul’s answer is very instructive for us. He explained that the call to be separate does not mean that they were to have no contact with sinners in the world. They were not called to leave the world the way the monks tried to leave the world. Separation is not achieved by avoidance of sinners in the world. The believer is called to separate by way of fellowship. There is a participation in Christ’s body that is unique only to believers. Paul was calling the church to think differently about the world than they did with regard to Christ’s church.
The world will always be what it is. It operates on its own system of values, attractions, and wisdom that often stand in opposition to the righteousness of God. By becoming Christians, we have left their fellowship and been joined to another. Our former love for the world has been replaced by love for Christ, but none of these truths entails a withdrawal from or refusal to mix in among the people of the world. This is why Paul explained to the Corinthians that because we live in the world there is no possible way to avoid mixing with unbelievers in daily life. Christians have an earthly citizenship, too, so long as they remain on this earth.
Christians are separate from the world, however, insofar as we refuse to join that way of life that stands in opposition to our heavenly citizenship. We are called to separate from the world by refusing to have fellowship with those who practice a way of life from which we have been delivered. We are separate in our heavenly status as Christ’s body and in the way that we behave before the world.
This is where the Corinthians had failed. They allowed into their fellowship someone who claimed to be a believer and yet lived in sexual immorality. The church’s refusal to separate from their former way of life had the consequence of joining together the church and the world. This is why Paul called them to separate from “anyone named a brother” (1 Cor. 5:11) who lives in a manner inconsistent with their new identity as the redeemed people of God. The Lord calls us to separate from those who claim to be believers and yet live in a way that contradicts the Christian faith and life through the practice of sin without repentance. We separate by breaking fellowship with them. The intimacy, care, and participation that exists among believers is not shared with those who refuse to repent and believe the gospel.
The Corinthian church was to accomplish this separation through church discipline. By casting the man back into the world, they were preserving their separate status as Christ’s people. Would they still cross paths with this man? Certainly. But now they no longer had Christian fellowship with him, and their willingness to maintain the purity of Christ’s church as believers in the world is what biblical separation is all about.