What can God do even in a vile situation?
God can move into a situation even as vile as this one, clear the deck, and make everyone once again in fellowship with the Holy God. He can intervene in sin's reverberations, restore the congregation, and cause the whole body to be enhanced by seeing His cleansing work.
Les explains that the Corinthian church confronted the man by laying out God's view of his actions and the reverberations it was having in the pagan city of Corinth. The result enhanced every one of them because they could see that God could move into a situation even as vile as this one, clear the deck, and make everyone once again in fellowship with the Holy God. It reverberated throughout the congregation. Les also highlights Paul's care for them in the sight of God, and contrasts that with glossing over the sin, which would have told the congregation he was no better than the rest and that it must not be all that bad.