Note 8 at 1 Cor. 5:10: Paul is writing about a common Bible theme, that of separation from ungodliness. However, Paul makes a very important point in preaching separation that many people miss. He says that our separation from errant believers must be stricter than from non-believers. In other words, we can tolerate some things from unbelievers that we should not tolerate from those who profess to be born again.

It all comes down to a matter of who is affecting whom? If we are in a position where we can change the ungodliness around us, then we should seize the opportunity even as Jesus and Paul did (Examples: Mt. 9:9-11; 11:19) and share the love of God with a dying world. To be the salt of the world, we have to get out of the salt shaker. But we should never allow ourselves to be in a position where we are the one who is being changed (see note 3 at Acts 19:9, p. 688).

In a church situation, we should first utilize the disciplinary steps set forth by Jesus (Mt. 18:15-17), but if that doesn't work, we should purge out the sin before it infects others (see note 5 at Mt. 18:17, p. 277). Casual contact with the world is less damaging than communion with a brother or sister that is in rebellion to God.