If you want to understand the book of Isaiah, don’t read straight through it. You’ll get lost. The book isn’t arranged sequentially. It’s made up of eight major sections that oscillate back and forth between two distinct time periods.

The first chronological period is the Assyrian crisis in Judah, under the reigns of Ahaz and Hezekiah. The expanding Assyrian empire is encroaching on the land of Israel. Ahaz attempts to appease the Assyrians, and compromises the nation’s devotion to God. His son Hezekiah then attempts to be faithful to God and resist the Assyrians as he faces the threat of annihilation.

The second period centers on the return of God’s people from Babylonian exile about 150 years later. Judah escaped the Assyrians, but was later conquered by the Babylonians. During the second period, Babylon is facing a threat from another rising power, the Medes and Persians. When they conquer Babylon, they’ll allow all the exiles to return to their lands. Some of the passages that speak to this second period come from just before the return, while others come after it. Still others take this time as their point of departure and look ahead into future events.

The fact that one book speaks to two periods so far apart in time naturally raises the question of whether more than one person wrote it. Biblical scholars of all theological persuasions have various opinions on this question. Some believe that the book had just one author, Isaiah the son of Amoz, and a later editor that adapted some of his material for later contexts. Others hold that Isaiah wrote chapters 1–39, while an anonymous later prophet and poet wrote chapters 40–66, in a style like Isaiah’s. And still others argue that there were actually three contributors: Isaiah; a later author who wrote chapters 40–55 towards the end of the exile; and another who wrote chapters 56–66 after the return.

Whether the book was the work of one, two, or three authors, it’s now a literary unit. The interweaving of writings from different periods makes the book difficult to understand when read straight through. However, it also enables us to appreciate the coherent story about God’s relationship with His people.

Major Sections in Isaiah

I ISAIAH 1–12

Poetic oracles and historical narratives about the earlier time period in the late 8th century BC—the Assyrian crisis during the reigns of Ahaz and Hezekiah (Isaiah 1).

II ISAIAH 13–23

Poetic oracles addressed to surrounding nations at various time periods (Isaiah 13). These oracles cover both time periods. The first oracle, against Babylon, speaks to the situation that comes last. But this placement pull the themes developed later in the book forward into the beginning of the book.

III ISAIAH 24–27

A short collection of oracles with a worldwide perspective. The judgment prophesied is cosmic. These oracles are spoken from the vantage point of the later time period, in the mid-6th century BC (Isaiah 24).

IV ISAIAH 28–33

Six long oracles, spoken in the earlier time period. Each pronounces a “woe” on the leaders of Judah for their reliance on Egypt for protection against Assyria (Isaiah 28).

V ISAIAH 34–35

A second brief collection of oracles in which the later historical situation is once again addressed (Isaiah 34). Cosmic judgments are described and the restoration of God’s people is promised.

VI ISAIAH 36–39

Historical narratives of Jerusalem’s deliverance from the Assyrian invasion, and of King Hezekiah’s recovery from a deadly illness, in the earlier period (Isaiah 36). The second narrative includes a description of how some Babylonian emissaries visited Hezekiah. This narrative is out of sequence chronologically within this section. It should really come first. But because it’s been placed last, it creates continuity with the section that immediately follows, by a common reference to Babylon.