2 Corinthians 7:8-9

8But even if I made you sad by my letter, I am not sorry about that. At one time, I was sorry that I had written it. I saw that my letter had made you sad. But you were sad only for a short time.

9So now I am happy, but not because my letter made you sad. No, I am happy because it made you turn away from wrong things. You became sad as God wanted you to be sad. So, when the letter made you sad, we did not really hurt you.