When I read this I remembered that Paul had written an earlier letter, rebuking the congregation for not acting in the case where a member was guilty of adultery. He had relations with his father’s wife, something that God had condemned. The other members had not dealt with matter. Apparently, they were proud of their church when they should have felt shame that this type of thing was in the church and root it out.
Paul called on them to do what needed to be done. He reminded them that they were not to keep company with such a person. His letter was very frank and it had the desired effect. The Corinthian believers repented. Their pride had turned to mourning and sorrow. Paul didn’t regret writing the letter because it produced godly sorrow.
Sometimes we have to do what is necessary what is best for others–no matter how hard or painful it may be. Paul revealed his motive for writing the first letter. It was not for the sake of the man who committed the wrong or his father whom he had wronged but for the sake of the church. He did it because he cared. Sometimes what we do might seem harsh to someone but we do it out of love. Tough love.