At the end of the Book of Job, God speaks. Whether there was a booming echo, we can't be sure, but it sure shuts Job up. For all of his yammering throughout the book, once God starts speaking, Job pretty much goes silent. All he says is that he's heard of God before (let's hope so!), but had never really seen him.
Sounds pretty simple, right? Enter God. End story.
Not so much. In some ways, Job is basically saying "I had to see it to believe it." But he can't have really seen it, since God is unknowable. Isn't that the whole point of the story? The authors just spent the whole book talking how God is a figure who works in mysterious ways, and who owes humanity no explanation. And now…God comes in and explains himself? What gives?
On the other hand, Job does finally gets it at the end. What does he get? That he can't understand everything. Job finally realizes that God's scope is way beyond his comprehension.
One last question, just to get you thinking: What do you think about Job being restored to his former glory? Is the book saying that if you complain enough, God will come down and give you back what was taken from you? Would the moral have been more powerful if Job had been left in the ashes?