During Prophet Isaiah’s lifetime the home country of the Jews was divided between the kingdom of Judah and the kingdom of Israel. The split happened after King Solomon had died, and ever since the two kingdoms had been at odds.
Now Judah’s King Ahaz was threatened by Israel’s King Pekah. King Pekah made an alliance with the Syrian King to overturn the kingdom of Judah. Naturally, King Ahaz became extremely anxious about the impending war.
In this situation God spoke words of encouragement to King Ahaz and the people of Judah by saying that the planned invasion of Israel and Syria won’t happen. In order to confirm the prophecy, God asked King Ahaz to request a sign from Him. You would think that King Ahaz jumped on the occasion, happily choosing a supernatural phenomenon showing the world that God was with them. However, for reasons unknown to us, King Ahaz refused to cooperate. His official statement (Isaiah 7:12):
But Ahaz said, “I will not ask; I will not put the Lord to the test.”
Here is Isaiah’s response to King Ahaz’s reaction (Isaiah 7:13-14a):
“Listen well, you royal family of David! Isn’t it enough to exhaust human patience? Must you exhaust the patience of my God as well? All right then, the Lord himself will give you the sign.”
So, the Lord insisted on choosing a sign, since this was not really just about King Ahaz but about every son and daughter of Adam and Eve. A sign of universal magnitude was to be given to the entire world. And here is the sign God chose (Isaiah 7:14):
“Therefore the Lord himself will give you a sign: The virgin will conceive and give birth to a son, and will call him Immanuel.”
In other words: “Here is a sign confirming that I, the Lord, am with you: a pregnant virgin will give birth to a son. The Son’s name is “I Am with you”.
Virgins don’t get pregnant, so this supernatural phenomenon serves as the sign. However, the name of the virgin’s son is equally remarkable: “I Am with you” contains God’s name “I Am”. This unusual name choice conveys that a pregnant virgin will give birth to the Son of God. When Virgin Mary gave birth to a baby boy 700 years later, Isaiah’s stunning prophecy was clearly fulfilled.
The sign of the virgin birth stands out and is different from any other demonstration of God’s involvement in human history. Supernatural phenomena like the parting of the Red Sea show God’s unlimited power. God born as a human baby shows His desire to be near us, so near that He becomes our relative born into a human family, Mary’s and Joseph’s family. This relative of ours has a name: “The One who saves”, also known as Jesus.