The exact meaning doesn't matter.
The gist is that the LORD is what He is. He will be what He will
be. Mortals cannot contain Him in a box and say He must be like
this, or He must be like that, or He cannot be like this.
In one of the most 'majestic' account from the Old Testament,
1 Kings 19:
11 He said, Go out and stand on the mountain before the Lord, for
the Lord is about to pass by. Now there was a great wind, so
strong that it was splitting mountains and breaking rocks in pieces
before the Lord, but the Lord was not in the wind; and after the
wind an earthquake, but the Lord was not in the earthquake; 12and
after the earthquake a fire, but the Lord was not in the fire; and
after the fire a sound of sheer silence. 13When Elijah heard it, he
wrapped his face in his mantle and went out and stood at the
entrance of the cave.
In this episode, God was not in any of the powerful elements.
Elijah actually 'saw' God in the sound of sheer silence. Wait a
minute .. how can you hear sheer silence? 
