ildad was the second of Job's friends to speak up. He was just absolutely certain that pure men would receive only good things and comfortable treatment from the hand of God (Job 8:6 & 20). His was a health and wealth gospel.
But, even if Bildad was right on target with his philosophy, he had no one to apply it to. Job says as much in his response, which we will get to in the next chapter (Job 9:2). It might be true that God will give blessings to men & allow no problems into their lives... if they are pure & perfect. But, who is pure & perfect? It is a category of none.
Some of what Bildad said was no more than a regurgitation of the words of his companion, Eliphaz (Job 8:5 & 5:8). Bildad also put heavy weight on what he considered to be the wisdom of history (Job 8:8-9). And, according to his interpretation of it, only wicked men had problems as heavy as Job's.
While it is true that there are many examples of evil men who have suffered greatly as a direct result of their own wickedness, it is also true that sometimes God's children suffer greatly despite their obedience... and sometimes, specifically because of their obedience. If you don't get anything else from the book of Job: get that.