2 Corinthians 7:8-10

Even if my letter made you sad, I am not sorry I wrote it. At first I was sorry, because it made you sad, but you were sad only for a short time. Now I am happy, not because you were made sad, but because your sorrow made you change your lives. You became sad in the way God wanted you to, so you were not hurt by us in any way. The kind of sorrow God wants makes people change their hearts and lives. This leads to salvation, and you cannot be sorry for that. But the kind of sorrow the world has brings death.