Job is done talking to the friends. He has argued his innocence to Eliphaz and gotten a demon's theology in return. He has argued his integrity to Bildad and gotten the fathers' library aimed at him like a weapon. He has described the impossibility of the courtroom in chapter nine and found himself, at the end of it, still in the ash heap with no mediator and no answer and no relief from the static between him and the God he cannot stop addressing. And so in chapter ten he does the thing that is either the bravest or the most desperate act in the book, depending on which side of the hedge you are standing on. He stops explaining himself to men and starts cross-examining God.

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