Matthew 18:17 (New International Version)
17 If they still refuse to listen, tell it to the church; and if they refuse to listen even to the church, treat them as you would a pagan or a tax collector.
This is the end of the line. Your brother or sister wrongs you. Step 1, verse 15, you take the issue up with them one-on-one. If that doesn’t resolve the matter, Step 2, verse 16, you take one or two others to assist. If there is still no resolution, Step 3, you take it to the church. If that fails, what?
Certainly, an unrepentant person should not be permitted to play a public role in the church, in its worship and service. In fact, Jesus says to “treat them as you would a pagan or a tax collector”. Now Craig Blomberg, in his commentary on Matthew, points out that this treatment is not as severe as it is sometimes made out to be. It is not “excommunication” or “disfellowshipping”. That was how the religious leaders of the day might respond to “traitorous” tax collectors and “unclean” pagans. But how did Jesus treat “pagans” and “tax-collectors”? With compassion. Such ones should not be abandoned or shunned, but reached out to and invited to repent.