This chapter begins with a change of tone (as if there were another author taking over—hint, hint). Instead of threatening people with wrath, God tells them to be comforted.
Jerusalem has already suffered more than double the punishment for her sins.
A voice cries out, saying that God's highway should be prepared in the desert and wilderness. All the valleys will be raised up and the hills and mountains will be lowered, and God's glory will be revealed in front of everyone.
Another voice tells Isaiah to cry out, but a puzzled Isaiah asks what he's supposed to cry out. The voice says he should say that all people are like grass—they live and then they wither when God's breath blows on them. But the word of God lives forever.
The people should go up onto the holy mountain of Zion. God will come to comfort and lead them, like a shepherd taking care of his sheep.
Fly like an Eagle
Isaiah asks a bunch of rhetorical questions illustrating how great God is. God is, as Isaiah already knows, super duper great, having measured out all the oceans and the earth in the hollow of his hand and weighed the mountains and hills.
Obviously, God didn't learn his knowledge or wisdom from anyone else. All the animals and trees of Lebanon aren't enough to provide and fuel a burnt offering to him.
The nations are nothing to God, just a few drops in the bucket.
God can't be compared to any idols, which are just cobbled together from material things.
He sits above everything, watching people hop around like grasshoppers below, and making princes and kings pass away almost as soon as they start their reigns.
Isaiah tells Israel not to wonder if God knows what it's doing. God doesn't get tired or weary, he's always aware.
Even young people get tired sometimes. The people who serve God will be strengthened by his inexhaustible power, though, as he lifts them up with wings like eagles.