Scripture does call for believers to be separate from the world, but this word has been so badly misused it has led to the abandonment of Christian duty as often as its fulfillment. The separation Scripture calls for involves not withdrawal from the world but a moral distinction. Separation of the believer to something. It is a separation to Jesus Christ, to His Kingdom, and to His service.
The problem of man that Jesus came to remedy was the moral one — i.e. man is a sinner who cannot be righteous or just by his own works. When God fixes our sin problem by paying its penalty, He calls us out of sin into life as new creatures in Christ. We are “new” men with a “new birth,” hence we are called to be separate from the world.
This new life of separation is to a new purpose. It is not a retreat from life, but a transfer of loyalty from our old life to our new, from a dedication to life in Adam to life in Jesus, who Paul called the “last Adam.”
The separate life of the believer should be one of focused activity, in which righteousness is our standard and the glory of God is our purpose. We yield nothing that is God’s to the world. We are separated as part of a new people to a cause that demands intense and dedicated activity. We yield nothing that belongs to our Lord and King. Christian separatism, rightly practiced, should strike fear into the hearts of nonbelievers. Christian retreatism actually enables them.
As believers, we have a responsibility as citizens of the Kingdom of God and His Christ. We obey His laws and further His claims. We do not compromise or back down or fail Him. As believers, we are separated from the world and self-service to our calling in the Risen Lord.