As a God of promise, God not only speaks his promises into existence, he speaks his promises into fulfillment. We see this throughout time and throughout his word. This Advent, as we await the coming of our Lord and Savior, we are happy to bring you a series of articles highlighting the multifaceted ways God has fulfilled his promises through the birth, life and resurrection of Christ.

What is the significance of God’s promise that Christ will be born of a virgin? Is it significant because of Mary’s example of purity or something else entirely? As we draw into the season of Advent and the contemplation of Christ’s coming, we do well to also contemplate the role of this specific promise given to God’s people first in the book of Isaiah and fulfilled through Christ’s birth.

Shortly after Isaiah is called to be a prophet, wars and rumors of wars come upon the kingdom of Judah, and it’s king, Ahaz. Isaiah 7 tells us that when Ahaz and his court hear the armies of Syria and Ephraim are mounting against them, their hearts “shook as the trees of the forest shake before the wind” (Isa 7:2). In response to Ahaz’s fear, God sends Isaiah to prophesy words of comfort.

God promises to give Ahaz anything he wants; there is no sign too big or too small for him to do.

Isaiah goes out to Ahaz with his son Shear-jashub (who is himself a walking, breathing prophecy because his name means, “A Remnant Shall Remain”), and tells Ahaz not to fear. Even though Syria and Ephraim are plotting against him in their hearts, what they plan will not come to pass. Syria will not succeed, and Ephraim will be destroyed. Then Isaiah ends his words of encouragement with a very important line, “If you are not firm in faith, you will not be firm at all” (Isa 7:9). Isaiah closes with a call to faith, to believe in the Lord, and to trust that God will protect his remnant. But what we see from Ahaz is quite the opposite.

Ahaz remains fearful even after all the great words of comfort from Isaiah. So God speaks to the king again and offers to give him a sign of his faithfulness and love. “Ask a sign of the LORD your God; let it be deep as Sheol or high as heaven” (Isa 7:11). God promises to give Ahaz anything he wants; there is no sign too big or too small for him to do. But Ahaz doesn’t bite. He doesn’t take God up on his offer. He doesn’t believe that God will protect his remnant. Yet even though Ahaz doesn’t ask for a sign, God still gives him one, and in response to Ahaz’s unbelief, the Creator of the Universe offers an unbelievable promise. A virgin will be with child(!), and this child will be called “God with Us” (Isa 7:14).

In this way, faithless Ahaz stands in the place of the whole world. We did not ask for signs or want them, but God promises to save his remnant with the virgin-born son of Mary. With this promise, God will make foolish the wisdom of men, and he will accomplish his salvation through the lowliest, and indeed, most scandalous ways. God does not combat the impending armies of Satan with might and power, but with the weakness of a babe. God does not choose a glorious vessel to carry this child, but a lowly virgin from Nazareth, pregnant before wedlock, and shamed because of it. But unlike Ahaz, when Mary hears the promise of God to save his people, she believes and confesses, “Behold, I am the servant of the Lord; let it be to me according to your word” (Luke 1:38). Even when God promises her the most peculiar and scandalous of signs, the only thing she has to say is “Amen,” which is, “Yes, yes, let it be so!” because nothing is impossible with God.

God does not combat the impending armies of Satan with might and power, but with the weakness of a babe.

It isn’t any merit or worthiness on Mary’s part that we honor her for. She is called blessed, in the words of the Magnificat, because of what God has done for her. He has given her faith and a song. He has looked upon the humble estate of his servant. He has shown mercy to those who fear him, and he has helped Israel in remembrance of his promise (Luke 1:46-55). Through both Ahaz’s unbelief and Mary’s belief, we see our God working to keep us according to his promises. Even when the world has been faithless with God, God remains faithful to the world.