First off, I would ask whether the view that Christians should never succumb to illness is one that lines up with the witness of Scripture. I firmly believe that the answer is "no". As I mentioned previously, everyone born on this earth either has died or will do so -- and some of those deaths will be caused by illness. Death is our lot in life and something has to kill us. To assert that we should expect to be healed of every single disease is to try to paint over the fact of our mortality. It's simply nonsensical.
But what, one may ask, of suffering that does not lead to death? The most obvious biblical example is that of Job -- who loses first his property, and then his children, and then his health, at God's allowance if not at his pleasure. Job and his wife discuss the proper response to Job's suffering:
Then his wife said to him, “Do you still hold fast your integrity? Curse God and die.” But he said to her, “You speak as one of the foolish women would speak. Shall we receive good from God, and shall we not receive evil?”In all this Job did not sin with his lips. (Job 2:9-10)Shall we receive good, and not evil? The implication is that to demand only good as our lot in life is foolish at the very least, and perhaps sinful. And although the context is different, this passage reminds me of Jesus' words in the sermon on the mount -- that God makes the sun to rise for both the evil and the good, and sends rain on both the just and the unjust (Matt 5:45). There are some things that are simply part of the human condition. The weather takes no notice of our righteousness or lack thereof. Neither do natural disasters. Why should disease, a natural disaster of a different nature?
At this point certain Christians might object to the example of Job, who, after all, lived pre-Christ. I believe that the Old Testament speaks to Christians just as much as the New -- but for those who may not, let us turn to the new covenant and see what it says about suffering. There are a few passages which I think it is helpful to examine.
1. 2 Corinthians 1:3-7
Blessed be the God and Father of our Lord Jesus Christ, the Father of mercies and God of all comfort, who comforts us in all our affliction, so that we may be able to comfort those who are in any affliction, with the comfort with which we ourselves are comforted by God. For as we share abundantly in Christ's sufferings, so through Christ we share abundantly in comfort too. If we are afflicted, it is for your comfort and salvation; and if we are comforted, it is for your comfort, which you experience when you patiently endure the same sufferings that we suffer. Our hope for you is unshaken, for we know that as you share in our sufferings, you will also share in our comfort.There are a few things to note here:
(a) We remember that Christ himself suffered, suffered greatly, suffered even unto death. If God himself in human form suffered, is it reasonable to expect that we mere mortals will not?
(b) We see that when a Christian suffers, in some spiritual/mystical (but real) fashion he or she is sharing in the suffering of Christ. Suffering has the power to further unite us to our Lord. This is not insignificant.
(c) the prevailing assumption of the passage is not that God will deliver us from suffering, but that he will comfort us in our suffering. Those are two very different things, although one may at times encompass the other. Note also that sharing in Christ's suffering enables believers to both share in each other's suffering and facilitate each other's comfort.
2. Philippians 3:8-11
Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith— that I may know him and the power of his resurrection, and may share his sufferings, becoming like him in his death, that by any means possible I may attain the resurrection from the dead.We see a similar theme here of joining in the sufferings of Christ. An interesting variation, of course, is that Paul wishes to become like Christ in his death so that he might be sure of attaining the righteousness that comes through faith and the resurrection from the dead. In some respects, suffering is (or can be, if we allow it to be) good for our souls.
3. Romans 5:1-5
Therefore, since we have been justified by faith, we have peace with God through our Lord Jesus Christ. Through him we have also obtained access by faith into this grace in which we stand, and we rejoice in hope of the glory of God. Not only that, but we rejoice in our sufferings, knowing that suffering produces endurance, and endurance produces character, and character produces hope, and hope does not put us to shame, because God's love has been poured into our hearts through the Holy Spirit who has been given to us.Again, we see that suffering has a purpose: it is a refiner and a character-builder. It is well and right to pray that God will heal us of our afflictions. But we should not be focused so exclusively on that longed-for healing that we miss what God is doing with us and in us, in and through our suffering. Romans 8:28 assures us that God causes things to work for our good, and that he can bring good out of evil. Sometimes this will mean relieving us of our suffering. Sometimes it won't. We are assured that God is working for our benefit and his own glory in both of those cases.
4. In general, the New Testament is replete with instructions on how Christians are to behave and believe when they are enduring suffering and affliction. The presence of these instructions presupposes that Christians will encounter suffering and affliction; again, these things are part of the human existence.
An understanding that Christians should not suffer -- and that God is never glorified in our suffering -- is not only contrary to the biblical witness but is completely ahistorical. Christians have always suffered. Read any hagiography; I'll bet you double-or-nothing that the saint in question suffered, perhaps greatly. I will also bet that along with their suffering there is a testimony as to its value.
Let us consider the following testimony from our spiritual forebears:
St. Vincent de Paul:
If we only knew the precious treasure hidden in infirmities, we would receive them with the same joy with which we receive the greatest benefits, and we would bear them without ever complaining or showing signs of weariness.St. Madeline Sophie Barat:
As iron is fashioned by fire and on the anvil, so in the fire of suffering and under the weight of trials, our souls receive that form which our Lord desires them to have.St. Ignatius Loyola:
If God sends you many sufferings, it is a sign that He has great plans for you and certainly wants to make you a saint.St. John of the Cross:
The road is narrow. He who wishes to travel it more easily must cast off all things and use the cross as his cane. In other words, he must be truly resolved to suffer willingly for the love of God in all things.St. Teresa of Avila:
Suffering is a great favor. Remember that everything soon comes to an end ... and take courage. Think of how our gain is eternal.St. John of Avila:
Dear brothers and sisters, I pray God may open your eyes and let you see what hidden treasures he bestows on us in the trials from which the world thinks only to flee. Shame turns into honor when we seek God's glory. Present affliction become the source of heavenly glory. To those who suffer wounds in fighting his battles God opens his arms in loving, tender friendship. That is why he (Christ) tells us that if we want to join him, we shall travel the way he took. It is surely not right that the Son of God should go his way on the path of shame while the sons of men walk the way of worldly honor: "The disciple is not above his teacher, nor the servant greater than his master."To accept suffering with joy is difficult; to dismiss it as spiritually worthless is foolish. We are commanded to pray for healing; we are commanded to suffer with grace and in hope. Christian suffering is not an anomaly; rather, it is often the very means by which we are brought closer to God, and in which we give him all the glory.