God proceeds from all this destruction onto another vision of peace in the future. The stump of the tree of Jesse (Jesse being the father of King David and a Bethlehem resident) will see a single shoot sprout out from it—just like the holy seed hidden in the stump from earlier.
God's spirit will rest on this shoot—the shoot we understand now is actually a person (descended from the House of David, it's implied). The shoot-person will be blessed with knowledge, wisdom, power, and reverence before God.
This person's not going to judge just by what his eyes and ears tell him. Instead, he's going to use true righteousness to judge everyone, giving the meek and the poor their fair shake.
His words will be like a weapon, striking down all evil. Righteousness and faithfulness will be like the belt holding up his clothes.
The kingdom that he rules over will be a holy mountain—like Jerusalem—where the wolf won't prey on the lamb (snuggling up with it instead). All predators and their prey—lions and calves and the rest—will cease to be enemies.
Bears are going to go vegetarian and graze with the cows, and children will be able to play with snakes.
All killing will end, totally, and the entire world will have knowledge of God.
The root of Jesse—the same holy one just mentioned—will stand up and be a signal to all the nations of the world, and live in a glorious house.
God will recover all of his own people, who have been exiled throughout the world, in places like Assyria, Ethiopia, and Egypt.
He will gather together all the outcasts from Israel and Judah together in one place.
Judah and Ephraim will stop fighting, and will instead go attack the Philistines and people further east (we're assuming this is before all that wolves-snuggling-with-sheep stuff kicks in).
The Ammonites, Edom, and Moab are going to feel the pain, too. They'll all bow down and be obedient in the end.
God will destroy "the tongue of the sea of Egypt" and build a way to cross over it (presumably for the Jewish exiles to go back home). There will also be a highway leading from Assyria back to Israel and Judah for the exiles trapped there, too—just as there was for the Israelites Moses led out of Egypt centuries before.