Paying attention to the historical context will always mean that the theological purpose becomes clearer, which, in turn, matters very much if the living Word of Scripture is going to impact our lives today. We have noted that Isaiah’s time was one of immense political upheaval across the ancient near east, when all the traditional spiritual and moral values were being questioned and reassessed. The long period of peace and prosperity under Uzziah began to break up after his death, and new challenges faced the kings of the Davidic dynasty—Jotham, Ahaz and Hezekiah—in Jerusalem.

Judah had always been a comparatively small nation, forced to depend on Yahweh for her security. Indeed, she was always strongest when she was most dependent. But with the people of the land increasingly exploited by the rich elite, and the rulers consumed with greed and self-seeking in both the religious and political life of the community, the challenge of Assyrian domination of the area posed serious questions. Though these issues were often viewed as essentially political or social, Isaiah’s ministry uncompromisingly defined them as spiritual. What will Judah, the people of the covenant, ultimately put their trust in? Where will they look for help? On what will they base their confidence? The question is posed in precisely those terms in 36:4, at the climax of the first section of the book. However, it is asked numerous times in various forms throughout the prophecy, and its realities are never very far away.

The choice is a stark one. Will Judah follow the ways of the nations all around her, trusting in diplomacy and alliances, relying on her own political wisdom and shrewd policies to preserve her status and security? Or will she rely on the promises of her sovereign Lord, Yahweh, bound to her by covenant oath, and so put her confidence in God alone? It is a choice with which every Christian is familiar, whenever life becomes challenging, whether at a personal level, or in a congregation, or on a national or international scale. Whom will we trust—God or ourselves?

Isaiah has often and rightly been designated the Old Testament prophet of justification by faith, the gospel prophet. We tend to narrow such a reference down to the proclamation of God’s justifying grace on the basis of the substitutionary atonement of the suffering servant (e.g. Isa. 53:4–6). That is of course the heart of the doctrine, as it is the heart of God’s great rescue plan, and Isaiah expounds it with great clarity as he calls for the response of repentance and faith. But we should also remember that justification by faith is a way of life, since being a justified sinner, a Christian believer, consists in a single and exclusive reliance upon the promises of God for the whole of one’s earthly existence.

The way into the Christian life is also the way on. The title of Scott Hafemann’s study The God of Promise and the Life of Faith2 sums it up so well, and the book itself is a magnificent whole Bible exposition of this great theme. So, this was the lifestyle question Judah had to face, as do we all. Are the promises of God a true and reliable foundation for life in this world (and the next), or do we have to look elsewhere for our confidence and security? In a nutshell, the choice is between divine promises and human policies.

By way of illustration, we can note that in the part of the book devoted to Isaiah’s own context (1–39) there are two parallel historical incidents, each given considerable coverage, which illustrate the issues facing the king of Judah and his people. They are dealt with in two diametrically opposite ways. The first comes from the reign of Ahaz and is the content of chapter 7. Syria and the northern kingdom of Israel had formed a coherent policy against Assyria in the form of an alliance that they wanted Judah to join. Her refusal led to a determined attempt to liquidate Judah as an independent dynasty, to topple the Davidic line and impose the son of Tabeel as a puppet king, draining all of Judah’s considerable resources into the alliance (7:1–6). Ahaz faces a very powerful force and is staring his own downfall in the face. But he is given a word from the Lord through Isaiah: ‘keep calm and don’t be afraid. Do not lose heart … It will not take place, it will not happen’ (7:4–7).

As with every word of God, there comes a great accompanying challenge. Will Ahaz believe it and so act upon it, or not? The issue could not be expressed more clearly than by Isaiah’s statement on behalf of God in 7:9b (which might be a strong candidate for the big idea of the first part of the prophecy), ‘If you do not stand firm in your faith, you will not stand at all.’ Faith is the only way to be established.

Ahaz, however, has already rejected the way of faith and is not going to turn back now. 2 Kings 16:5–9 tell us that he ignored God’s gracious promises and chose instead to commit himself to Tiglath-Pileser, the king of Assyria, as his vassal, using the silver and gold from the Lord’s temple to buy his assistance. It could hardly be clearer. He rejects the covenant Lord of his fathers, in order to submit himself to a pagan overlord. Judah can only suffer terribly as a result.

Ahaz even refuses God’s gracious offer of a sign to strengthen his faith (7:10–13), but by embracing Assyria as his help he has invited in a swarm of bees to ravage every part of the land, ‘to shave your head and the hair of your legs, and to take off your beards also’ (7:18–20)—total humiliation and subjugation. The history of the reign of Ahaz is the commentary on this text.

In contrast, Hezekiah, his son, later faces an Assyrian invasion of even more terrifying proportions, mopping up the fortified cities of Judah and advancing on Jerusalem itself (36:1–2). He too receives a gracious word from the Lord, ‘Do not be afraid of … those words with which the underlings of the king of Assyria have blasphemed me.’ (37:6) Instead, God promises deliverance and the imminent assassination of Sennacherib, Hezekiah’s tormentor (37:6–7).

We know from chapters 30 and 31 that Hezekiah has been dabbling in an attempted alliance with Egypt, disparagingly referred to by Isaiah as ‘Rahab the Do-Nothing’ (30:7), in order to attempt to extricate himself from being Assyria’s vassal. But now, to his great credit, he believes God’s promise and affirms his faith by laying out the whole perilous situation in prayer (37:15–20). In response, God gives more detailed promises, a sign to strengthen faith and a clear divine affirmation, ‘he will not enter this city … I will defend this city and save it, for my sake and for the sake of David my servant!’ (37:34–35). And he does! ‘Then the angel of the LORD went out and put to death a hundred and eighty-five thousand men in the Assyrian camp’ and Sennacherib returned to Nineveh where his sons cut him down with the sword in the temple of his god (37:36–38).

In this way, Isaiah presents the central theological issue facing him and his hearers at the very heart of his prophecy. But we must also note that from the beginning to the end, this particular historical event is set in the wider context of God’s promises and purposes for his people, not just in the restricted environment of Jerusalem in the eighth century BC, but universally and eternally.

Isaiah 1 presents us with a summary of the situation in Judah, both as to its symptoms and causes. There is corruption in every area of her national life: political, religious and social. ‘Your whole head is injured, your whole heart afflicted’ (1:5b). The climax of this devastating exposé is its focus on Jerusalem as representative of the whole people of Judah. ‘See how the faithful city has become a harlot!’ (1:21).

Unfaithfulness to her covenant obligations will produce two divine responses. The first is, ‘I will turn my hand against you’, but that is immediately shown to initiate a purging away of dross and removal of all impurities. ‘Afterwards you will be called the City of Righteousness, the Faithful City’ (1:25–26). Here are the two cities, the unfaithful and the faithful city, so that one way of understanding the theological agenda of the prophecy is to trace its answer to the question, ‘How is the faithless city to become the faithful city?’ Or, on the broadest canvas, ‘How is the earthly Jerusalem to become the New Covenant?’ One Bible study book on Isaiah’s prophecy is entitled Two Cities for very good reasons.3

It will take the whole of the Bible to spell out God’s detailed answers to that question, but it is all here, in embryonic form at least, in Isaiah’s amazing book. The immediate answer is only by a miraculous intervention of God’s compassionate grace, which centres on the Messianic figure, who dominates the whole book, as Immanuel, the suffering servant and the conquering warrior.

David Jackman, Teaching Isaiah: Unlocking Isaiah for the Bible Teacher, ed. Robin Sydserff, Teach the Bible (Ross-shire, Scotland; London, England: PT Media; Christian Focus, 2010), 25–30.

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