# He stood

This means that Yahweh stopped walking and stood still, not that he stood up from a seated position.

# measured the earth

Possible meanings are 1) the word translated as "measured" can be "shook" or 2) he surveyed the earth the way a conqueror would before assigning portions to his governors.

# he looked and shook the nations

The nations shook with fear because he looked at them. This is the fear a guilty person has when he is afraid that the person looking at him will punish him.

# eternal mountains ... everlasting hills

"mountains that have existed since the beginning of time ... hills that will exist until the end of time."

# Even the eternal mountains were shattered

"Even the eternal mountains crumbled" or "He shattered even the eternal mountains" 

# His path is everlasting

"He walks along an ancient path"