John Piper explains Elihu’s view of suffering in Job 36:6–15
The helpful thing in these verses is that Elihu makes clear that there is such a thing as a righteous person who still has sin that needs to be revealed and rooted out. To call a person righteous does not mean that the person is sinlessly perfect. There is a “righteous sinner.”
This is helpful because God himself called Job a righteous man in 1:1, and Job won his argument on the basis of his reputation as a righteous man. And yet at the end of the book Job repents and despises himself. So Job is righteous (by the testimony of God!) even though he has sin remaining in him. He is not among the wicked.
Elihu looks at these two groups of people, the wicked and the righteous, and he distinguishes the different roles that suffering has in each. We’ll start reading at verse 6:
He does not keep the wicked alive, but gives the afflicted their right. He does not withdraw his eyes from the righteous, but with kings upon the throne he sets them for ever, and they are exalted.
Now if he had stopped there, he would have sounded exactly like Eliphaz: the wicked suffer and the righteous prosper. There is a sense in which this is true in the long run. But the question plaguing Job is why the righteous suffer in the short run. So Elihu goes on in verse 8:
And if they [that is, the righteous] are bound in fetters and caught in the cords of affliction [so Elihu admits right away that the righteous are not always with kings on the throne; they do suffer], then he declares to them their work and their transgressions, that they are behaving arrogantly. He opens their ears to instruction, and commands that they return from iniquity.
In other words the righteous are far from sinlessly perfect. There is much of the old nature left in them, and from time to time this old nature of pride breaks out in actual sinful behavior—as it did with Job when he accused God of being his enemy. This is what Job repents of at the end of the book.
Suffering Refines the Righteous
Elihu’s teaching, then, is that affliction makes a righteous person sensitive to his remaining sinfulness and helps him hate it and renounce it. Suffering opens the ear of the righteous (v. 10). The psalmist said the same thing in Psalm 119:71, “It was good for me that I was afflicted, that I might learn thy statutes.” There are dimensions of godliness that the righteous can only learn through affliction.
So the new slant that Elihu gives is that the suffering of the righteous is not the fire of destruction but the fire that refines the gold of their goodness. For the righteous it is not punitive but curative.