Therefore the Lord himself will give you a sign: The virgin will be with child and will give birth to a son, and will call him Immanuel.
The backstory: Saul, David, and Solomon were the three greatest kings Israel had. They ruled in succession over a unified kingdom when Israel was at the height of its power. After Solomon’s death, the kingdom split into north and south, with the northern half going by the name Israel (and sometimes Ephraim) and the southern half going by the name Judah. Israel (the northern kingdom) had nothing but wicked kings; Judah (the southern kingdom) had a mix of good and wicked kings. Israel lasted a couple of centuries and then was overrun by the Assyrians. Judah lasted a couple of centuries longer than Israel but was eventually overrun by the Babylonians.
Israel and Judah did not get along very well, and at this point Israel had allied itself with Aram (one of its neighbors to the north) and was threatening to attack Judah. The king of Judah at this time was Ahaz, who was not one of their good kings. Even his name sounds evil.
So at the start of Isaiah 7 we find Ahaz and all the rest of Judah shaking in their boots because word has reached them that Aram and Israel have teamed up and are headed their way. Ahaz is seriously contemplating the possibility of seeking an alliance with Egypt. Considering the history that the people of Israel had with Egypt, things must be looking really bad if seeking an alliance with Egypt seems like a good idea.
Isaiah prophesies to Ahaz: “Be careful, keep calm and don’t be afraid.” Those two kings from up north are just smoldering stubs of firewood that are about to be snuffed out; “within sixty-five years Ephraim will be too shattered to be a people”. (Isaiah sure has a way with words, doesn’t he?) He then asks Ahaz to ask God for a sign that this will come true. But Ahaz refuses; he does not care about God and will not put him to the test.
So Isaiah says that God will give him a sign anyway: The virgin will be with child. Now in this context he is not talking about a virgin birth; the word “virgin” here simply means young woman. The young woman in question is his (Isaiah’s) wife. He goes on to say that very soon–before this child is old enough to know right from wrong–both Aram and Israel would be laid waste. There would then be a very troubled time for Judah as the Assyrians came upon them.
Sure enough, the prophecy was fulfilled. Everything went down just as Isaiah said it would. And then everybody forgot all about this little prophecy. And it just sat there. For seven hundred years plus, it just sat there.
And then a virgin–an actual virgin, not just a young woman–gave birth to a child.
A virgin girl named Mary and her husband-to-be Joseph were living up in the northlands of Israel. They were part of a sect that was intentionally waiting for the coming of the promised Messiah. Sects such as theirs were all over the place at that time, and many were completely disengaged from temple life.
All of a sudden Mary turned up pregnant. Now, these people did not know anywhere near what we know about biology, but they knew enough to know that virgins don’t get pregnant. It doesn’t take a degree in molecular biology to understand that. Joseph knew there had to be another man in the picture somewhere. He could have had Mary publicly shamed, or possibly stoned as an adulteress. But he didn’t want to go there, so he made up his mind to divorce her as quietly as possible so that she could marry the child’s father.
Then one night an angel appeared to Joseph in a dream. “Do not be afraid to take Mary home as your wife, because what is conceived in her is from the Holy Spirit. She will give birth to a son, and you are to give him the name Jesus, because he will save his people from their sins.” (Matthew 1:20-21)
Matthew continues: “All this took place to fulfill what the Lord had said through the prophet: ‘The virgin will be with child and will give birth to a son, and they will call him Immanuel’–which means, ‘God with us.’ ” (Matthew 1:22-23)
Here Matthew reaches all the way back to that long-forgotten prophecy from Isaiah. Its significance in relation to the birth of Jesus was not lost on him. He even sharpens the focus of Isaiah’s prophecy: “virgin” means not just a young woman but an actual virgin, and “they” will call her son Immanuel. Not just the young woman, but all the people.
Twice the Lord said “Do not be afraid”. First he said it through Isaiah to the king Ahaz. But Ahaz refused the sign, and it did not go well for him or his kingdom. Then he said it again through the angel to Joseph. Joseph believed, and became the earthly surrogate father to Jesus Christ, the Son of God. Through him, deliverance came, not just for the kingdom of Judah in a troubled time in its history, but for all the world. Not from a besieging army, but from the curse of sin which holds all people and all creation in bondage.