Strength For the Weary

Advent 3A | Isaiah 35

Grace to you and peace from God our Father and the Lord Jesus Christ. Amen.

Have you ever had a moment when you just felt worn out—truly worn out? Not just the end-of-the-day kind of tired, but the kind of exhaustion where your hands shake a little, your knees feel unsteady, and you wonder how you’re supposed to keep going. Maybe it was after bad news. Maybe it was in the middle of a long stretch of stress. Maybe it was standing beside a hospital bed, or facing a problem you couldn’t fix.

Most of us know what that’s like. You try to be steady, but your strength isn’t what it used to be. You try to stay hopeful, but worry keeps creeping in. Sometimes life simply wears you down, and it feels like you don’t have much left to stand on.

Isaiah was writing to people who felt the same way. They were anxious. They were afraid. Their hands were weak, and their knees were shaky. Into that kind of fear and fatigue, Isaiah speaks these words:

 “Strengthen the weak hands, and make firm the feeble knees. Say to those who have an anxious heart, ‘Be strong; fear not!’” (Isaiah 35:3–4a).

But how will weak hands be strengthened? How will trembling knees be made firm? How will anxious hearts “fear not”? Isaiah will show us this morning what God does for us when we can’t take another step.

I. God Comes to Save the Weak (vv. 3–4)

Notice in verse 3 first how Isaiah describes the people: they have “weak hands… feeble knees… fearful hearts.” These people have nothing left. They no longer have the strength to fix their situation or the courage to face it. Their hands can’t lift a weapon. Their knees can’t hold them up. Their hearts beat faster with fear than with hope. Isaiah is describing a people who are in no condition to save themselves. 

Judah was watching the world collapse around them. The northern kingdom had already fallen under the crushing might of Assyria. The next campaign would sweep toward Judah—everyone knew it. They were staring down the possibility of invasion, exile, and ruin. Their fear was the honest terror of a nation with no military strength, no political leverage, and no ability to stop what was coming. Their condition was helplessness. 

There is a connection here. Isaiah is describing us. We, too, stand where Judah stood—exhausted and fearful by life in a fallen world. Just like ancient Judah, we are in no position to do anything to save ourselves. We, too, have weak hands—the things we can no longer control, the burdens we can no longer lift. We have feeble knees—places where we cannot stand as firmly as we once did. We have anxious hearts—fears about the future, about our families, about our health, about our world. 

Into that condition God speaks a pair of commands: “Strengthen” and “make firm” But notice how the strengthening happens. Not by telling the fearful to try harder. Not by urging them to be brave. God strengthens His weak people through a Word spoken into their fear.

And what is that Word? Not advice. Not coping strategies. It is a promise entirely based in God’s action: “Behold, your God will come… He will come and save you.” Judah cannot save itself. Fear will not be conquered by resolve. Salvation will not come through their strength but through God Himself showing up. 

So Isaiah’s proclamation becomes God’s Word to you today: “Be strong; fear not… your God will come.” The solution to your weakness and fear is that God comes to save. Our weakness does not scare Him away—it is why He draws near. God comes to save the weak. Are you weak? Then God comes to save you! God will come, not because you have regained your strength, but because He comes precisely for the weak. Strength does not arise out of your weakness. Strength arrives—because God does. When faced with your own weakness, you are not called to look to yourself, but to the God who comes.

II. God Transforms The Weak (vv. 1–2, 5–7)

If verses 3 and 4 tell us that God will come to save the weak, the rest of the chapter shows us what happens when God actually arrives. Isaiah lifts our eyes from trembling hands and shaking knees to an unexpected scene: “The wilderness and the dry land shall be glad; the desert shall rejoice and blossom like the crocus.”

Isaiah begins with geography because the land reflects the people who inhabit it. Judah felt like a desert—dry, exhausted, unable to produce life on its own. But when God comes, the barren places are the first to change. A wasteland turns into a garden. Death gives way to life. What sin has ruined, God begins to renew and transform.

Isaiah continues: “Then the eyes of the blind shall be opened, and the ears of the deaf unstopped; the lame man shall leap like a deer, and the tongue of the mute sing for joy.” This is the pattern of God’s salvation. He does not simply take weak people and command them to be strong. He makes them strong by coming and renewing all things. Where God comes, life springs up. Where God speaks, strength returns. Where He shows up, weakness becomes the very place where His power rests.

These are the signs Jesus pointed to in our Gospel reading when John the Baptist asked, “Are You the One?” Jesus replied not with arguments but with evidence—He healed the blind, lifted the lame, opened deaf ears, and loosened mute tongues. In other words: “Isaiah’s promise is happening. God has come. Salvation is here.”

If your life feels like a desert—tired, dry, worn thin—then Isaiah’s promise is for you. When God comes to save the weak, He does more than encourage them; He changes them. He renews us. God restores the very places sin has damaged. He heals the heart so that it can trust again. He strengthens the will so that it can stand again. He enlivens the new man so that obedience becomes possible where it wasn’t before. Renewal means God gives us strength where we are weak; He rekindles faith, hope, and love where sin has chilled the soul. And He does this not by demanding effort from you, but by giving Himself to you.

The promise “He will come and save you” is not left floating in the air—it is delivered in specific, tangible places where Christ gives Himself to you. In Holy Baptism, He unites you to His death and resurrection and gives you a new heart that trusts Him. In His Word, He speaks strength into your weakness and gives what He commands. And in His Supper, He feeds you with His own Body and Blood, so that His life sustains your life, His strength upholds your weakness, and His presence drives out fear. “Your God will come and save you”—and this is where He does it.

III. God Leads The Weak Home (vv. 8–10)

Isaiah now shifts the scene again: God not only restores His people, He also leads them somewhere.  “A highway shall be there, and it shall be called the Way of Holiness.” For a people staring down exile, this was unimaginable. The roads from captivity back to Zion ran through hostile lands, wilderness, and danger. No one could walk that journey alone. Yet Isaiah says a highway will appear—a raised, cleared road—something no human hand could construct across a desert. 

Isaiah also tells us what kind of road it is. It is not the path of the mighty, the clever, or the morally impressive. It is a road only the redeemed can walk. Not because they are better, but because God Himself has ransomed them. He has purchased and claimed them as His own. “Your God will come and save you” (Is 35:4). 

Jesus proved by word and deed that He was the One to come. And what did He come to do? Isaiah foretold it: God would come personally to save—to transform and renew, to ransom and redeem. But the ransom is not theoretical. God buys His people back with a real price. The Holy Way is opened by blood. Christ walks into the wilderness of our sin and fear, carries our weakness to the cross, and lays down His life as the payment that secures our return. His resurrection is the moment the highway is cleared—death pushed aside, sin broken open, the way home opened forever.

Since God has purchased and claimed His people, nothing unclean, nothing threatening, nothing predatory can set foot on that highway. “No lion shall be there… but the redeemed shall walk there.” The enemies that once terrified them are now gone. The God who comes to save also guards the journey with His own power. The redeemed shall walk there—and you are among them. The danger remains real, but your road is guarded. 

This road leads somewhere. “They shall come to Zion with singing; everlasting joy shall be upon their heads.” Isaiah sees homecoming. He sees the end of fear. He sees joy that overtakes them before they reach Zion itself. Zion, that’s home. The place where God dwells among his people. And then comes the final promise: “Sorrow and sighing shall flee away.” Not reduced. Not managed. Not balanced. Gone. Isaiah ends not in exile, not in fear, but in joy that never fades and a home that cannot be taken away. A new creation. 

There are moments when life simply wears you down, and it feels like you don’t have much left to stand on. Isaiah’s message speaks to you this morning: “Be strong; fear not!” Not because you are strong, but because your God comes to save you. The God who comes to save the weak, and who strengthens what sin has ruined, is the same God who carries His people all the way home. 

He has come in the flesh, He has walked your road, He has carried your weakness all the way to the cross, and He has opened the way home by His empty tomb. And He continues to come—today, here, for you. Not metaphorically. Not symbolically. Truly. He strengthens weak hands with His Word. He makes feeble knees firm in Baptism. He lifts up the weary in His Supper, feeding you with His own Body and Blood, giving you forgiveness, life, and strength for the journey. These are not reminders of a distant hope. They are the places where the risen Christ Himself comes to you, leads you home, forgives you, and steadies you.

So when your strength fails, when your courage buckles, when you feel you cannot take another step—be strong; fear not. Come again to where He has promised to be. Here your God comes to you. Here He strengthens you. Here He keeps you on the way home.

May the peace of God, which surpasses all understanding, guard your hearts and your minds in Christ Jesus. Amen.