Apostol § 170

Brethren, he who established us with you in Christ and has anointed us is God, who has also sealed us and given us the Spirit in our hearts as a deposit. Moreover I call God as witness against my soul, that to spare you I came no more unto Corinth. Not that we have dominion over your faith, but are helpers for your joy; for by faith you stand... But I determined this within myself, that I would not come again to you in sorrow. For if I make you sorrowful, then who is he who makes me glad but the one who is made sorrowful by me? And I wrote this very thing unto you, lest, when I came, I should have sorrow over those from whom I ought to have joy, having confidence in you all...