The book of Isaiah is sometimes described as the gospel of the Old Testament or “the fifth gospel”. It is extensively quoted in the New Testament – 194 NT passages contain allusions to verses from 54 of Isaiah’s chapters – most of the book. These quotations are used in several different ways but here are two examples: John the Baptist is introduced by Luke with a quotation from Isaiah 40 and when Jesus begins his teaching ministry at the synagogue in Nazareth he quotes from Isaiah 61.
But who was Isaiah and when did he speak? Isaiah himself is introduced as the “Son of Amos” (1:1; 2:1; 13:1) and spoke during the reigns of several kings from the Northern Kingdom of Judah: Uzziah, Jotham, Ahaz and Hezekiah in the 8th century BC. You can read more about them in Kings and Chronicles.
There is some scholarly debate as to whether or not the book of Isaiah is made up of multiple authors which we should at least be aware of. As far back as 1155 a commentator suggested that the second part of the book could be attributed to an anonymous prophet (“Deutero-Isaiah”) in Babylon while Israel was in exile, a claim restated by German scholars in the late 19th century. In this view, 40-66 wouldn’t be seen as a prophetic utterance of Isaiah in the 8th century BC speaking ahead to the 6th century, but as a contemporary speaking to explain the fulfilment of Isaiah’s previous prophesy. This prophet addresses Jewish exiles in Babylon, names the Persian ruler Cyrus; contains different theological themes and has a different poetic style. On the other hand, others point out that there is continuity of language, there is no Jewish tradition or manuscript evidence indicating any second author and that prophetically addressing the exiles-to-be in Babylon 150 years earlier is little in comparison to predicting the crucifixion 500 years later.
Whichever view we conclude with, it’s easy to see that the book can be divided into two large sections, 1-39, which paints a picture of judgement and then 40-66, which tells a story of hope.
Largely, the first section (1-39) describes God’s judgement in response to the rebellion, idolatry and oppression of the poor coming from the lofty “old” Jerusalem. To the city of rebellion God is sending nations – Assyria and later Babylon – who will be a purifying fire, eventually carrying away the people into exile (1-12; 13-27; 28-39) but in the end leaving behind a repenting “new” Jerusalem. In the midst of this is the promise of a new king called Emmanuel. The nations may be the means of God’s judgement, but they will also themselves be held to account. The section concludes with a rebuke to Jerusalem’s leaders, who are accused of resorting to their old nemesis Egypt for salvation and then sidling up to the rising power Babylon in another political manoeuvre.
In the second section (40-66) we turn to the theme of hope, hope that the covenant promises would be stabilised, hope for a new king and hope that Israel will become a blessing to the nations. The scene dramatically changes to be one where the exile is over and the people are invited back to Jerusalem. In this section Israel is described as “God’s servant” and we find the famous “servant songs”, most notably the suffering servant of Isaiah 53. God is on a mission to restore the people of Israel and be a light to the nations empowered by the spirit – how? The servant is to be rejected, beaten, killed as a sacrifice of atonement – and then becomes alive again. Two ways of response are laid out: humility and repentance or rejection. Those who respond in the former are God’s servants who inherit his kingdom and all the nations are invited to become part of this covenant family.