"All discipline for the moment seems not to be joyful, but sorrowful; yet to those who have been trained by it, afterwards it yields the peaceful fruit of righteousness."
Affliction comes in many forms and for many reasons. Poor health may result from poor choices we have made in regard to caring for our bodies. On the other hand, an illness may come through no fault of our own -- from genetics, virus or other mysterious reason. As much as we don't like to admit it, sometimes God allows an ailment to bring us to a point of complete dependence upon Him. When we have nothing else to lean on, we learn how important our relationship with Him is to our well being. There is no one who can minister to us as God can. When we are suffering, it is not a joyful time. We only want the pain to be over. And who can blame us for not enjoying pain? However, when we submit to the Lord, we gain something that the unbelieving world can never understand. We share in Christ's suffering, becoming more like Him. (Philippians 3:10)