2 Corinthians 7:8-9; 2 Corinthians 7:12-13

8 Even 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—

9 yet 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.

12 So even though I wrote to you, it was neither on account of the one who did the wrong nor on account of the injured party, but rather that before God you could see for yourselves how devoted to us you are.

13 By all this we are encouraged. In addition to our own encouragement, we were especially delighted to see how happy Titus was, because his spirit has been refreshed by all of you.