Why did Paul write to the Corinthians instead of waiting to visit them?
Paul wrote to the Corinthians because he did not want to come and experience sorrow or grief from those who should have brought him joy. He feared hearing about problems in the church that would make him sorry rather than joyful, so he wrote with many tears and anguish of heart.
Les explains that in verse 3 Paul wrote this same thing lest, when he came, he should have sorrow or grieve from them of whom he ought to rejoice. In other words, he would hear things taking place in the church that made him sorry instead of joyful. In verse 4 Paul says he wrote out of much affliction and anguish of heart, with many tears. Les notes Paul was not overemphasizing; his heart was broken and he was in tears because of what he was hearing from the congregation at Corinth. Les also points out Paul had confidence that his joy was the joy of them all, and his whole mental concept concerning this carnal church was that they could grow and become real trophies of God's grace in spite of all the pressure. These early Christians were under pressure from the Jewish element and the pagan element, and only a precious few were able to come into the liberty of Christianity.
And I wrote this same unto you, lest, when I came, I should have sorrow from them of whom I ought to rejoice; having confidence in you all, that my joy is the joy of you all.