The Sign Fulfilled

This sermon was preached by Pastor Ted Carnahan for the Fourth Sunday of Advent on Sunday, December 21, 2025.

Grace, mercy, and peace be with all of you from God our Father and from our Lord and Savior Jesus the Christ. Amen.

I'm guessing that there's at least one person in the room today who is extremely confused because they thought it was still the Fourth Sunday of Advent and here we are reading the story of Christmas. What is going on? Well, we'll get to that on the 24th. So please be here for worship that night.

But the story that I want to reflect on today is not actually the story of the birth of Jesus itself, but rather the prophecies that surround it. Because the birth of Jesus the Messiah took place in this way: When his mother Mary had been engaged to Joseph, but before they lived together, she was found to be with child from the Holy Spirit.

This idea that Jesus Christ, the Messiah, is born in this particular and unusual way is one that modern people have often rejected as being mythological. But for us who are being saved, it is vital. We include the virginal conception and birth of Jesus Christ in all of our creeds and we confess it boldly and unapologetically. Why? Well, that's what I want to get to today.

Joseph's Reaction and Mercy

Here's Mary and Joseph and she has conceived a child and Joseph's reaction is quite a natural one. In fact, he could have been a lot angrier. He planned to dismiss her quietly, but he didn't have to dismiss her quietly.

He is an older man and he was hoping for this woman to be a follower of the God of Israel. And yet as a follower of the God of Israel, if she had had marital relations before they had been married, she would be a sinner. And according to the Old Testament Law, she would have been eligible to be executed by stoning, by throwing rocks at her until she died.

So his willingness to put her away quietly actually is an act of profound mercy because if she had engaged in marital relations before being married, she would have been eligible for the death penalty. Joseph, a righteous man and unwilling to expose her to public disgrace or even death, plans to set her aside when suddenly he has a dream.

He has just set his mind upon this idea when he has a dream, and in the dream an angel comes to him, a messenger from God. And this messenger comes and tells him,

"Don't be afraid to take Mary as your wife, for the child conceived in her is from the Holy Spirit. She will bear a son and you are to name him Jesus, for he will save his people from their sins."

Now keep in mind on that side of the cross of Jesus, it's hard to see how a man would be born who could save his people from their sins. But Matthew, the apostle, tells us,

all this took place to fulfill what had been spoken by the Lord through the prophet.

Ahaz, Ask for a Sign!

So what is it exactly that the prophet says? Let's turn for a moment to reflect on Isaiah chapter 7. Here we have a totally different situation and yet one that is parallel not just to the situation of Mary and Joseph, but parallel to us in our day.

The people of God, under the leadership of King Ahaz, are under terrible threat by not one, but two kingdoms. This terrible threat threatens to destroy the people of Judah and scatter them.

And into that situation, Isaiah the prophet comes to King Ahaz and says,

"Ask a sign of the Lord your God. Let it be as deep as Sheol or as high as heaven."

Isaiah commands King Ahaz to ask for a sign from the Lord, but Ahaz refuses, which is strange. He is not in a position of power. He's not in a position of favor. Things are not going well for him and his kingdom. But he refuses.

Why would a king refuse to ask for a sign? Well, for one part, there's definitely the idea that the Old Testament tells him not to. Think of Jesus in the wilderness as he's taken up to the top of the pinnacle of the temple. The evil one, the accuser, Satan, tells him, "Throw yourself down for the psalm says, that if you cast yourself down, that the Lord's angels will not allow you to dash your foot against a stone."

And Jesus' response is, "You shall not put the Lord your God to the test." That's not something that Jesus just came up with off the top of his head. But he's quoting the Old Testament. And in the Old Testament, it says, "Do not put the Lord your God to the test."

And so Ahaz here is feigning piety. He is pretending to be holy when he is not an especially holy man. And so he says, "I will not ask. I will not put the Lord to the test."

Ahaz's False Piety

There's only one problem with that, Ahaz. He told you to. He specifically said,

"Put me to the test. Ask for a sign. Any sign you want and it will be given to you. Ahaz, if you are doubting that God has the power to rescue his people, to bring them safety and security in this life, simply ask me for any sign, be it as high as heaven or as deep as the domain of the dead.

"No matter what you ask for, I will make sure it happens and you will see it with your own eyes.

"And then you can believe in the Lord. You can believe that these signs that he does are proof that God is real and that he cares about his people and he's going to take care of you."

Ahaz understands that. He is so pious that he's unwilling to ask for a sign. Is that he knows that to follow this God, if he is revealed to be real, will demand everything from him. And he wants to be in charge of his own life.

Well, Isaiah is frustrated. And I'd be frustrated too if I were Isaiah. He says,

"Hear then, O house of David, is it too little for you to weary mortals that you must weary my God also?"

Let me put that in the Ted Carnahan translation: Ahaz, I am so sick and tired of you. And not only am I sick and tired of you and your fake piety, but I am so sick and tired of you that I know that God is sick and tired of you. Stop pretending like you believe and acting so holier than thou.

And then he says this: the Lord's going to give you a sign anyway. Here's God's sign. You can go look for it if you want to.

The Prophecy of Emmanuel

"This young woman is with child and shall bear a son and shall name him Emmanuel."

That's the prophecy that the angel is speaking of in Matthew chapter one, our gospel reading today.

Notice though, that the name the angel gives to Joseph to give to Jesus is not Emmanuel. It is Jesus. Yeshua. Which actually is the name Joshua. Meaning God saves.

There's more to this prophecy though, more going on here than just there's going to be a kid born and he's going to have this particular name. That's not a very difficult sign to do.

But Isaiah includes this from the Lord. He says,

"He shall eat curds and honey by the time he knows how to refuse the evil and choose the good. For before the child knows how to refuse the evil and choose the good, the land before whose two kings you are in dread will be deserted."

In other words: there is a woman right now who is pregnant. Already pregnant. She's going to name her kid Emmanuel. And by the time this kid is old enough to start eating solid food, really early in his life, less than probably a year old, he can eat curds. He can eat wild honey. He can have these things. He's not just living on breast milk. By the time that happens, by the time he knows to eat good and not bad, a small child, the two kings that you are afraid of, Ahaz, will be gone. Their kingdoms will be deserted. They will come to nothing.

Ahaz, you're so proud and so false pious that you are unwilling to ask God to provide a sign. But not only is God going to provide you a sign, but he's also going to take care of your little kingdom problem here by getting rid of these other two kings.

And so there will be no way for you to deny that God is the one who put these men to flight and deserted their kingdoms. There'll be no way for you to claim that that came any other way than by the hand of God alone. You who are so unwilling to be rescued, so proud in your willingness to try to stand in the world without God, look what I'm about to do for you anyway.

Fulfillment in Jesus Christ

Now we can turn back to Matthew. Because as we come to Matthew now, the situation that Isaiah was preaching in is not all that different than the situation that the angel is referring to.

(Not in Joseph's case. Joseph was actually quite a righteous man. A man who sometimes is called St. Joseph the worker because he was a laborer. Maybe a carpenter. I think more likely today we would call a man with his skill set a contractor, or a builder.)

And this man just wants to do what's right by himself, his family, and also by Mary. And the angel comes and says, "Don't be afraid to take her as your wife for the child conceived in her is from the Holy Spirit."

Think of how remarkable and odd a claim that is.

Yeah, no, she hasn't had marital relations, Joseph. Actually, the child is God's. Uh-huh. Sure.

But somehow, by the gift of God, Joseph believes. He sees the angel saying, "Do not be afraid." And he clings to the truth of that promise and says, I will believe that. This child is by the Holy Spirit. And I shall name him Jesus. Yeshua. Joshua. After a great victor and a leader of God's people. Joshua from the Old Testament.

All this took place to fulfill what had been spoken to the Lord through the prophet. But wait a minute, Pastor Ted. You just said that we were talking about King Ahaz. Isaiah was talking about King Ahaz. And he was talking about this young woman who was going to have a child named Emmanuel. And that all this stuff was going to happen 600 years before the birth of Jesus. And that's right!

So which one is it? Is it talking about, is Isaiah prophesying to Ahaz 600 years B.C.? Or is he prophesying about Jesus around about year one? And the good Lutheran answer is yes. Both of those!

Because the prophecy given by Isaiah to King Ahaz is fulfilled in his time in the sign that God promises to him. Otherwise, it would make no sense at all. "Hey, Ahaz, everything's going to be okay. These kings are going to go away. Because 600 years from now, there's going to be a baby born who's going to save his people from their sins." That doesn't make any sense.

He says to Ahaz: you will see this in your lifetime. Actually, you'll see this in the next year and a half or so. These kings who are bothering you and God's people, they're going away. Their lands are going to be deserted. God is going to deal with them for you. You don't have to lift a finger. You don't even have to ask. It's taken care of.

But also, this prophecy fulfilled in time, is also fulfilled ultimately in the birth of Jesus Christ, who is the ultimate Emmanuel, who truly is God is with us. And so Joseph awakes from sleep and trusts the promise.

Application to Our Lives

People of God, are you too proud to rely upon God on a regular basis? Like King Ahaz, too unwilling to ask for God for you, what he has apparently been willing to do for many others?

Because there are so many who believe in God, and yet in our society, it seems like more and more people, they don't call themselves atheists. They just say that they are religiously unaffiliated. Or when they ask if they have a church, they say, well, no, I have none. To the point where now demographers are starting to call those people Nones. Not "nuns" like, you know, white and black, dressed like a penguin, pray a lot. But Nones, N-O-N-E-S, they have no big beliefs about God.

And to that situation, God comes to us like He comes to King Ahaz and says: it doesn't matter whether you believe or not, because I am going to do for you what you were too proud to ask. Whether you like it or not, I am going to give you not just a sign, but its fulfillment. I am going to give you Jesus of Nazareth, born of a virgin.

"Behold, the young woman is with child. The virgin is pregnant, and she will bear a son, and you will name Him Joshua, Jesus. He will save His people from their sins. He will be Emmanuel." (Literally, God is with us.)

And that He's born of a virgin is not just some pious invention of the first century, but it is our very life. Because this One who is born of a virgin, who has a human mother as His mother, and the Holy Spirit coming upon Him to make Him the Son of God, this One shares in our humanity in every way. He feels and thinks. He has a human body and a rational soul. He hungers and thirsts. He laughs and cries. He is like us in every way except our inbuilt sin, the sin which forces us, in our pride, not to rely on God.

By His human mother, He inherits all of what it is to be human. And then, by God His Father, He becomes the living, incarnate Word of God.

This Word of God, who, going to the cross and willingly dying for us, becomes not just the atonement for Himself (for He had no sin) but becomes the fulfillment of all of God's commandments and the atoning sacrifice, for all of our sins, effective for the whole world through faith in Jesus Christ.

This is the miracle that we look forward to, that we anticipate in the season of Advent, that God is coming, not just as a miracle in time long ago, but He is coming to be with us now, to overcome all those obstacles which we place in the way of our pride and our sin, and simply to go and live for us and die for us and rise for us, so that we might be restored to life and relationship with God, that in Christ all things are renewed and made good, that we have His holiness, His righteousness, and His peace.

May you know that peace as you prepare for the coming of Christ at Christmas. And may the peace of God, which surpasses all understanding, keep your hearts and minds strong in Christ Jesus our Lord, to life everlasting. Amen.