https://www.biblegateway.com/passage/…
Ahaz was in a heap of trouble. Not from bill collectors or bad grades but from his neighbors to the north. In jealous anger Syria and Israel came down upon Judea, surrounded Jerusalem and were about to besiege it. All of this was allowed by God as punishment for Ahaz’s unbelief and idolatry, leading the people away from God. When they heard of the attack against them, they were afraid – so afraid that, “their hearts shook like the trees shake before the wind.” Really, they should have known better. All the times that God had delivered them, all the times that He had shown His mighty hand to save. In fact that is exactly what God wanted them to do – to remember, to repent. But they didn’t, they just shook. Still, God came with a promise for Ahaz and the people in verses 7-8 “It shall not stand and it shall not come to pass…” In fact, God said, within 65 years both of these menacing countries would be nothing but ashes. This might have seemed very hard for Ahaz to believe but God in His mercy offered to give him a sign. While Ahaz’s response might seem very pious and trusting, God’s answer reveals his heart – it was nothing but hypocrisy. He thought to say what God wanted to hear but still he doubted. So God Himself chose the sign, one higher than the heavens and deeper than sheol, the greatest sign that has ever been given: “Behold the virgin pregnant and bearing a son and she will call his name Immanuel.” Usually, if you want to assure someone of something that will happen in the future, you give them something now, like a downpayment on a car. That’s what God did when Gideon asked for a sign – he performed the miracle of the fleece to assure Gideon of His word. But here God has it flipped around – the sign that He gives was not to happen for about 700 hundred years. We aren’t told what Ahaz’s reaction was but I can imagine he well might have thought Isaiah was nuts – “what are you talking about you crazy prophet? the virgin pregnant? What does that mean? What good is that? How does that help me against Syria and Israel.” Isn’t that typical? How often do we, in unbelief think that God’s answer cannot help me with my problems. Perhaps it was so for Ahaz. If so, he was wrong. This was the perfect sign to behold, to cure him and all Judea of their shaking hearts because it is the surest promise of scripture.
God had been pointing his people to the promise of the savior for thousands of years. It was to this sign that He pointed Adam and Eve on the day they left the Garden of Eden. This was the promise He made to Abraham, Isaac and Jacob. This one promise was the sign for all people. It was their hope, their confidence and their joy. This sign was the best proof God could give to Ahaz because there never was nor ever would be anything more sure than the miracle boy – Immanuel, He who would save his people from their sins. In God’s eyes it was as good as done. This is why Isaiah says “if you are not firm in faith you will not be firm at all.” This is the sign to behold for shaking hearts because it cannot be shaken.