And if he refuses to hear them, tell it to the church. But if he refuses even to hear the church, let him be to you like a heathen and a tax collector. (Matthew 18:17, NKJV)
The church is to be fully engaged in trying to restore the Christian who has resisted private attempts to call him to repentance. If the Christian continues to refuse the church’s warnings to repent, a separation must occur. The unrepentant Christian is lost, but he is not the enemy of the church. Like other sinners, he must be admonished about his sin, not encouraged in his sin (2 Thessalonians 3:15). Normal social interaction must be ended, to help produce shame for his sin, and the necessary repentance (2 Thessalonians 3:6, 14). Thus, he is delivered over to Satan to destroy the flesh and, in this final effort, to save his soul. This social separation by each Christian also protects the church from the impure influences of a Christian who has no remorse for continuing to sin against the Lord (1 Corinthians 5:6-13).