For indicates that what is to be mentioned is an explanation of what was spoken in 2 Cor. 4:13-18. In this chapter the apostle tells us of the apostles' aspiration for the redemption of their bodies (vv. 1-8; Rom. 8:23), their ambition, their determination, to please the Lord (vv. 9-15), and their commission from the Lord for His new creation (vv. 16-21).