Paul, the apostle, wrote a letter to the Church in Corinth after he learned about a scandal. He cited the church's arrogance for not mourning the incident, and for not taking decisive action. The church should have removed the guilty person from fellowship.
1 It is actually reported that there is sexual immorality among you, and of a kind that is not tolerated even among pagans, for a man has his father's wife. 2 And you are arrogant! Ought you not rather to mourn? Let him who has done this be removed from among you (1 Corinthians. 5:1-2).
Instead of the usual private warning at first and then with two to three witnesses, Paul instructed them to remove the so-called brother from the fellowship. Why did Paul skip the protocols of Matthew 18:15-17? Because the knowledge of the scandal was well-known even to the unchurched. The church should make a firm stance not to tolerate sin in their midst.
I have also attached a Filipino-Tagalog version of the sermon.