Evidently members of the church in Corinth were suing one another, and Paul rebuked them for it.
He made them think about what they were doing,
“If then you have judgments concerning things pertaining to this life, do you appoint those who are least esteemed by the church to judge?” (1 Corinthians 6:4).
All the Corinthian Christians could think about was their problem with the other brother, and they did not realize how they were presenting the church to the world.
They needed to look beyond themselves and see the world watching the church.
What impression are you giving the world of the church?