With such a man do not even eat. Warn a divisive person once, and then warn him a second time. After that, have nothing to do with him. God's Word tells us that the sinning brother who refuses to repent of his sin must be removed from the circle of fellowship with God's people. We commonly refer to this as excommunication.
Excommunication involves cutting a person off from membership, fellowship, and communion.
In short, the unrepentant believer is to be treated like a non-believer because of his refusal to walk like a believer. As strong as this measure may seem, it's designed to bring the erring brother to full repentance and restoration, provided the congregation obeys and follows. We see the church in America is today almost void of any form of congregational disciplines, not to mention personal disciplines as well. The answer is we have fallen far from the holy standard God has set for His people to live, walk and worship by. Often today when godly leadership moves to set up disciplined goals for growth in holiness and purpose in Christ, violent reaction can often be seen.