This chapter was included as part of the single chapter covering our current chapters 16 to 22, or including chapters 6 through 12 of Isaiah. These verses conclude the prophecy against Assyria, and continue the reversal that Jehovah will visit upon the world. In the previous chapter, the millennial reign was described, where the Messiah would come to rule and peace would reign.
These verses are a song of praise for Jehovah and that promised salvation. It begins with the clear declaration that “O Lord, I will praise thee; though thou wast angry with me thine anger is turned away.” That is the message of the Assyrian invasion. It would be terrible, but it would end. This becomes the reversal of the oft-repeated phrase that the Lord was angry still and his hand outstretched still. In this future Messianic rule, there is no more anger.
Jehovah will become Israel’s strength and song. The returned righteous remnant will return not only physically, but also spiritually return, or repent. They will see Jehovah as their salvation.
In the previous chapter Isaiah has declared that all of the earth would be God’s temple, and this song of praise reiterates that when it declares “great is the Holy One of Israel in the midst of thee.”