Job 9

Job 9:33

"There is no umpire between us,
Who may lay his hand upon us both.

Job is clearly aware of the vast gulf between God and man.  This gulf is of both physical and authoritative distances.  First, there is an uncrossable physical gap between them.  There is no one who can bridge the gap between God's place in Heaven and man's tiny speck on Earth.  Since no one can span the gap, there is also no one who can keep God from crossing that gap to do what He wishes.

In that vein, there is also a huge gap in authority.  Job speaks of an umpire here, but my first thought is that a better word might be judge.  God's power, authority, and reasons are far beyond man's.  He can literally do anything He wants, and no judge can restrain Him.  He has the authority to do anything, so no judge can overrule Him.  And finally, He wrote the plan of the universe, so no one can tell Him that He's wrong.