What shall we say to these things? Something must be said because sickness and death are threats to faith in the love and power of God. And I regard it as my primary responsibility as a pastor to nourish and strengthen faith in the love and power of God. There is no weapon like the word of God for warding off threats to faith. And so I want us to listen carefully today to the teaching of Scripture regarding Christ and cancer, the power and love of God over against the sickness of our bodies.
I regard this message today as a crucial pastoral message because you need to know where your pastor stands on the issues of sickness, healing, and death. If you thought it was my conception that every sickness is a divine judgment on some particular sin, or that the failure to be healed after a few days of prayer was a clear sign of inauthentic faith, or that Satan is really the ruler in this world and God can only stand helplessly by while his enemy wreaks havoc with his children — if you thought any of those were my notions, you would relate to me very differently in sickness than you would if you knew what I really think. Therefore, I want to tell you what I really think and try to show you from Scripture that these thoughts are not just mine but also, I trust, God’s thoughts.
God controls who gets sick and who gets well, and all his decisions are for the good of his children, even if they may be very painful and long-lasting. It was God who subjected creation to futility and corruption, and he is the one who can liberate it again.
— John Piper, Desiring God, Jesus and Cancer, August 17, 1980