It's that time of year again ... the time when Isaiah 7:14 gets beat up like a rented mule. I read discussions of it every year, as I did again this morning, and am still not convinced that anything in the eighth century BC (when Isaiah was writing) can fulfill the prophecy of Isaiah in 7:14.
Isaiah 7:14 talks about a young woman who is a virgin and pregnant at the same time. The word "pregnant" is an adjective describing the virgin. She is not a virgin now who will become pregnant later. In the prophetic mind of Isaiah, she is both a the same time.
Many appeal to Isaiah 8:1-4 as a fulfillment of Isaiah 7:14, either partially or fully. The problem is that the prophetess of 8:1-4 is not both a virgin and pregnant. She is first one, then the other.
The question is usually brought up, How is the birth of Christ, seven hundred and thirty years later, a sign to Ahaz? The answer: It's not. It was not intended to be. Ahaz had already rejected a sign through a false show of piety, because he had already secured his hope through a foreign alliance. He was not interested in listening to God, and so God was not speaking to him.
The prophecy is given to a group of people, as indicated by the plural forms of the prophecy. It was intended to assure the house of David, and more broadly the nation of Israel, that Tabeel would not succeed in removing Ahaz from the throne, thus breaking the Davidic covenant.
The Davidic covenant would stand, and it would still exist seven hundred and thirty years later when the Son of David, Immanuel, would be born to a pregnant virgin.
So what of the reference in vv. 15-25 to the deliverance of the nation in the eighth century BC? If the prophetic mind of Isaiah sees the virgin as currently pregnant (which it does), his prophecy is made on the basis of that pregnancy. Isaiah does not know the time or the person (cf. 1 Peter 1:10-12). But he did know what he was saying.
There is only "God with us" which is what Immanuel means. And it certainly was not Maher-Shalal-Hash-Baz. It was none other than Jesus Christ who is our only hope, and who is the only hope for the nation of Israel.
It is further interesting that those who see a fulfillment in Isaiah 8:1-4 do not seem to want to see that fulfillmen in chapters 9-11 which are the conclusion of the Immanuel section of Isaiah. The reason they do not press that fulfilllment is because chapters 9-12 tell us that Immanuel will reign, and Maher-Shalal-Hash-Baz did not do that. I would suggest you can't have it both ways. If 8:1-4 fulfills 7:14, then it must also fulfill chapters 9-12. Of course, only Jesus fulfills 9-12, which again gives us increased basis for our hope in Christ.
As a side note, it is always interesting to me that people who see no need to see a literal fulfillment of OT promises to the nation fulfilled to the nation suddenly see Isaiah 7:14 as having to have some fulfillment to the person to whom it they believe it was made. These scholars, many of whom are good men, see no need for promises made to Israel to be fulfilled to Israel, but they insist that a promise made to Ahaz must be fulfilled to Ahaz. That seems inconsistent to me. It seems better to see Isaiah as making a promise about the Davidic covenant, ensuring the nation of Israel that God has not abandoned them because of Ahaz's foolish distrust and foreign alliances.
God will be faithful, and he will come to be with us, and to reign over his chosen people. You can count it.