In Isaiah Chapters 40 and 41 we have been exploring Who God Is. Here's what we know so far. God is Great! He delivered Israel; He is in control of world leaders; He is greater than idols. He provides. He protects. Let everything that has breathe praise the Lord.
Now, in Chapter 42, we learn more about God and His mysterious Trinity, specifically His Servant Jesus.
We now enter a new section of Isaiah. Most commentators distinguish two "halves" of the book. The dire prophetic judgements of the "Old Testament" half, with the tragic end of Israel and much of Judah by the Assyrians, and the more hopefully, Messianic, "New Testament" half in which Isaiah has amazingly accurate prophesies regarding Babylon. This second second begin with chapter 40.
This is the second of three events we see in the "historical interlude" in the middle of the book of Isaiah, all related to King Hezekiah. These are cross-referenced in II Kings 20 and II Chronicles 32.
This is the final chapter in the "woes and blessings" chapters (ch 24-35). This chapter is a direct contrast to the previous chapter 34. From Armageddon to the contrasting Kingdom of God and the blessings enjoyed for those who chose Him and are in His family.
In the Ryrie Study Bible's outline of Isaiah, Chapter 27-35 are labeled as denunciations against Israel and Judah, with the subtitle of "woes and blessings". We've spent the last few chapters dealing mostly with Egypt; but the focus shifts to Assyria.