2 Corinthians 7:8-9

8Even if I caused you sorrow by my letter, I do not regret it. Though I did regret it—I see that my letter hurt you, but only for a little while— 9yet now I am happy, not because you were made sorry, but because your sorrow led you to repentance. For you became sorrowful as God intended and so were not harmed in any way by us.