1. Israel will fill all the world with fruit (2-6)

God wept over the vineyard in Isaiah 5. Yet there was a redemptive purpose in it. He waters and watches over it continually. The briars and thorns, enemies of God's people, will also submit and make peace. In this way, the fruit of God's salvation will reach the whole world, starting from Jacob. This is our hope.

2. By this his guilt will be atoned for (7-13)

The Lord struck Israel to lead them to repentance, unlike the nations whom he would wipe out for attacking her. The fruit of repentance would be to remove all the idols from their land. After the return from exile, all such idols were in fact removed from Israel. Isaiah's generation would have to see the city desolate as they were people who needed to acknowledge the Creator. Yet in that day, a day to come, a great trumpet will signal the gathering of all God's faithful one by one, to come and worship the Lord in Jerusalem.