Chapter 7-12 The Coming One of The House of David.
It was in accordance with what God had told Isaiah at his calling that success would not be immediate. But Isaiah also knew that past revelation had shown that final deliverance must come through the house of David which had been established for ever (Isa 55:3; 2 Samuel 7:13; 2 Samuel 7:16; compare also Genesis 49:10-12). In this he had complete confidence. ‘God has said it, and will He not do it?' Thus he knew that his task must include the encouraging the house of David to faith in Yahweh, and the proclamation of the final success of that house. And it is in this that he now engaged himself in Chapter s 7-12.
Chapter 7 The Failure To Believe of the House of David, Resulting In God's Promise of a Great Sign and Remarkable Birth in the Future Restoring Of That House.
In this section from Isaiah 7:1 to Isaiah 8:10 great emphasis is laid on sons as being signs of what God is going to do. We have Sheerjashub (‘a remnant will return') in Isaiah 7:3, Immanuel (God with us') in Isaiah 7:14; Isaiah 8:8; Isaiah 8:10 and Maher-shalal-hash-baz (haste the spoil, speed the prey) in Isaiah 8:3-4. The first and third are sons of the prophet, the second a son of the Davidic house. The sons of Isaiah are a portent of the judgment that is coming, with the promise that a remnant will return (Isaiah 8:18). But Immanuel (God with us) is the hope for the future, the coming David, although He too will arise when times are bad.
Judah and Jerusalem are at this point being threatened with invasion by Syria and Israel, because they have refused to join an alliance against the Assyrians (see Introduction). But God is in favour of Ahaz's position in refusing to join the alliance and therefore encourages Ahaz by promising that if he will but trust in Yahweh he will have nothing to fear. God will be with him. And He even offers him a mighty sign.
However, Ahaz spurns the offer with the intention of appealing to Assyria for aid, and God therefore gives him instead a sign that he does not seek or desire, a sign which is a consequence of his refusal. It is a sign of rejection. For it is revealing that from now on his house, the seed born through him. are to be seen as rejected. God will no longer be with him. So the coming Messianic (Anointed) king whom Judah are expecting, instead of being a son of Ahaz, will be supernaturally born. A virginal young woman will produce a child, who will be called Immanuel (God is with us). The idea is that Ahaz' own seed will have been rejected, and replaced with God's seed. And through this child God will again be with His people. Meanwhile before such a child would even have time to grow up Syria and Israel will be destroyed, following which Judah will be devastated by Assyria.
We must recognise that this was a crucial moment in the life of the people of God. Prior to this they had remained independent, apart from times when Egypt had exercised their influence, which had been on and off and on the whole relatively benign, but from now on the choice was between independence and trust in God, or submission to the great empires to the north. This was the choice that lay before them. To put this in its historical perspective, Uzziah died around 740/739 BC, Assyria invaded Syria and Israel in 733-32 BC, probably only a year or so after this prophecy, because they had rebelled and refused tribute. Damascus fell in 732 BC, and Samaria in 722 BC. The question was, what would happen to Judah and Jerusalem?