For example, the oneness of the book is indicated by the expression, “the Holy One of Israel,” which appears 12 times in chapters 1 to 39, and 13 times in chapters 40 to 66, a total of 25 times; whereas it appears only 6 times throughout the rest of the Hebrew Scriptures.
... The remaining chapters, Isa 40 to 66, have as their theme the release from Babylon, the return of the Jewish remnant, and the restoration of Zion.