Chapter twelve begins a section of prophetic pronouncements against various nations. The section ends with a hymn of praise. Within the section, however, are four subsections. The first three (chapters 13-20; 21-23; 24-27) concern the nations around God’s people. Each section includes references to the coming judgment against the people of God. The final section contains six specific woes against God’s people and concludes with judgment against all nations, followed by the hymn of praise.
The heading of chapter seventeen concerns Damascus, the capital of Syria. And yet, it becomes obvious that the chapter is not just about Syria. Verse 1 concerns Damascus, but verse 2 concerns “the cities of Aroer,” which were in the region of Gad in Israel. By this time, historically, Israel has allied herself with Syria (see Isaiah 7:1-3) and by doing so, she means to conquer Judah. This is why Damascus (Syria) and Ephraim (Israel) are mentioned together in this chapter. Through their alliance, their fates have also become intertwined. Israel’s fall begins internally, like a sickness (vs. 4) but will be completed by outside forces (reapers and gleaners). Then, they will look to their God, but it will be too late.
Judah has looked to her fortified cities for protection, but they have failed. Though Israel visibly rots from within to the north, Judah is not learning anything. She has abandoned her fortified cities, but not looked to the one who can deliver her: the Lord. The nations chafe at God’s direction, and so do God’s people, but in the face of His overwhelming power, it does not make sense to rebel.