What is our life without joy? Without joy we can do nothing. We are like an instrument out of tune. An instrument out of tune it yields but harsh music. Without joy we are as a member out of joint. We can do nothing well without joy, and a good conscience, which is the ground of joy. A man without joy is a palsy-member that moves itself unfitly, and uncomely. He goes not about things as he should. A good conscience breeds joy and comfort. It enables a man to do all things comely in the sight of God, and comfortably to himself. It makes him go cheerfully through his business. A good conscience is a continual feast Prov. xv. 15. Without joy we cannot suffer afflictions. We cannot die well without it.
In his Commentary on 2 Corinthians 1:12