Some say that sin is the root of all sickness; but what about Job and Elisha? Job was greatly afflicted, but not because of sin. No, he was tested. Elisha died of sickness, but there's no indication of disobedience. He continued to serve and his bones were still holy enough to heal a man who fell upon them! Even Paul had an affliction.
No, sin is not the root of all sickness. God uses it to test us, to strengthen us, to direct us, and to correct us; but He also uses it to teach others, to reach others, to expose and emphasize the guilty, to motivate the lazy, and to remove the godly from what the wicked will endure. Literally, the godly die and the wicked live; but only, that He might punish them as pleases Him.
The righteous perish, and no man layeth it to heart; and merciful men are taken away, none considering that the righteous is taken away from the evil to come. Isa 57:1
His ways are not our ways, Folks. He thinks on a completely different level. Is it not more merciful to let a saved person suffer that others might be turned back? Yes, it is. Most who are His would rather suffer that more might be saved, but it would be mistake to think lightly of their suffering.
No, these afflicted saints are not less, and their sorrow is not immaterial. Sometimes being sick, and waiting for God can be the most important battle they wage. It may be the last battle, but it is still very necessary