God Shows Up with Some Questions of His Own
Job has questions. He doesn't say that he's never sinned. He says that his spiritual life doesn't correspond with his change of circumstances. In other words, he lived a very righteous life and enjoyed tremendous blessings. Then his blessings went away and were replaced by tremendous suffering, but (and this is really his argument) his spiritual life didn't change in such a way as to merit such a drastic change in his circumstances.
His friends ask, "So, why has all this happened?"
Job says, "I don't know."
If his friends had been wise, they would have said, "We don't know either."
But that's not what they say. They argue with Job, and here's a wise principle: never argue with someone who is in mourning. Logic doesn't often go hand-in-hand with grief.
Eventually, Job says, "I wish I could sue God. If only God would show up and we could talk about this man-to-man."
In chapter 38, Job gets his request. In fact, it's kind of funny and ironic. Elihu (another one of Job's friends) is in the middle of telling Job why God doesn't have to show up when God actually shows up.
If we misunderstand this next part of the story we'll end up with lots of bad theology.
God never answers Job's questions. God could have explained the first couple of chapters to Job. He could have told Job about the Upper Stage and the conversation he'd had with Satan. But he doesn't. He just asks Job a few questions of his own -- questions that Job cannot possibly answer.