Isaiah 26:3: Thou Wilt Keep Him in Perfect Peace
The following is a manuscript from a sermon preached on February 15, 2026 at Burning Bush Reformed Church in Grand Rapids, MI.
Isaiah 26:1 In that day shall this song be sung in the land of Judah; We have a strong city; salvation will God appoint for walls and bulwarks.
2 Open ye the gates, that the righteous nation which keepeth the truth may enter in.
3 Thou wilt keep him in perfect peace, whose mind is stayed on thee: because he trusteth in thee.
4 Trust ye in the Lord for ever: for in the Lord Jehovah is everlasting strength:
5 For he bringeth down them that dwell on high; the lofty city, he layeth it low; he layeth it low, even to the ground; he bringeth it even to the dust.
6 The foot shall tread it down, even the feet of the poor, and the steps of the needy.
Introduction
Good evening, church. It is, once again, an honor to preach the word of God to the people of God for the glory of God. This past Thursday evening, a precious young man in our congregation called me and I could hear worry, sorrow, and a sense of duty in his voice. He informed me that his one-year-old daughter had a seizure and that she was in an ambulance on the way to the hospital. Just the night before, at our mid-week service, my two-year-old daughter was hugging on his daughter. My wife was holding his daughter as she peacefully laid her head upon my wife’s shoulder for respite. In that moment, on the phone, I asked a few questions to assess the need and then, I said, “Brother, I remind you of God’s promise in Isaiah 26:3, ‘Thou wilt keep him in perfect peace, whose mind is stayed on thee: because he trusteth in thee.’” I reminded him that the Creator of the heavens and the earth is keeping him, his wife, and his daughter, even in times of great difficulty, in perfect peace. Today, we are reminded that although we will face times of discouragement, doubt, and despair we are kept in perfect peace by our perfect Savior.
Putting the Text in Context
We approach our text tonight by looking at the historical setting that Isaiah writes within. Isaiah served Judah beginning in 739 BC. He served under Kings Uzziah, Jothan, Ahaz, and Hezekiah. Recall with me that it was not until the year 586 BC that Judah was exiled into Babylon. Isaiah would have been dead for about 80-100 years at that point in history. This detail is important for us because our text tonight is in Isaiah 26 and it looks forward to the day that Judah returns from an exile that she has not yet experienced. For Isaiah, he provides this song to help Judah keep their mind on God although they will live in a foreign land, enduring times of discouragement, doubt, and despair. This explanation provides great application for our modern audience. Similarly, we are waiting on our arrival into Beulah Land, that is the Heavenly City that we shall inhabit one day. As we eagerly await that day, we too, will face times of discouragement, doubt, and despair but we, God’s covenant people, can continually sing the truths of Isaiah 26 and maintain peace of heart and mind, despite the external chaos that may exist around us. Now that we have looked at the setting, we want to look at the text.
Explanation
Tonight, we will briefly observe the truths of verses 1 and 2 before examining verse 3 more fully. The phrase “In that day” is a phrase used six times in Isaiah 24-27 to discuss the Lord’s victory, the fate of his people, the fate of his foes, and the strong city with open gates. “A song will be sung” to call to memory the covenant faithfulness of Yahweh even though Judah will exist in exile. They look forward to “a strong city” with salvation acting as her walls to keep the good in and the evil out. According to verse 2, the gates of this city are open to the righteous and those who keep the truth (faith). And we must point out that if this strong city is characterized by salvation, righteousness, and faith, it sounds a lot like the heaven we are to inherit. For this reason, many authors think this text has an eschatological feel to it.
Now, as we embark on verse 3, we note the citizens of the strong city possess peace. We want to break verse 3 down and see why we, people subject to discouragement, doubt, and despair, may have peace within. When we examine verse 3, we see a Who, What, and Why.
1) Who – Yahweh is the one doing the keeping.
Here, we ought to think of the words of Jesus in John’s Gospel:
John 10:28 And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.
John 17:11 And now I am no more in the world, but these are in the world, and I come to thee. Holy Father, keep through thine own name those whom thou hast given me, that they may be one, as we are.
The idea of “keeping” means to guard as one would a fortified city. Jesus prays that Yahweh would “keep [them] through thine own name.” Especially in the Old Testament, a person’s name represented the totality of their person and character. When Christ calls upon His Father to keep us through His name, He is saying keep them through the totality of You who are. Every attribute of God keeps us. His love, mercy, kindness, sovereignty, justice, incomprehensibility, eternality, etc. Every bit of who God is keeps us in perfect peace. Such a truth produces peace in itself.
2) What – Perfect Peace
Not only are the citizens of the strong city described as those who possess salvation, righteousness, and faith but also peace. The phrase “perfect peace” in the Hebrew is rendered “Peace, Peace.” This displays that perfect peace does not waiver or oscillate. It is not double-minded. How can this be? It is because perfect peace is only possible because it is founded on promises from a perfect Savior who does not waiver or oscillate. Christ, His person and work, is as steady as it gets. These promises, bestowed upon us by Him, include a strong city whose citizens possess salvation, righteousness, and faith.
3) Why – Whose mind is stayed on thee
Why are we kept in perfect peace? The text says “whose mind is stayed on thee.” When we contemplate the term “stayed,” we can think of it as unflinching, settled, and sustained. In his commentary on Isaiah 26:3, John Calvin makes a case that we should understand this phrase “whose mind is stayed on thee” as not referring to your mind staying on God but rather His mind staying on you, His church. He reasons that if “perfect peace” is dependent upon our mind continually “staying” on God, then we will never achieve it and this is not a promise but a hope dashing away like ash in the wind along with our fleeting thoughts. Instead, Calvin says that we are kept in perfect peace because God’s mind stays on thee. His mind is always, unceasingly, and without diminishing, stayed upon thee. Though it helps to keep your mind upon the Lord to promote peace, your peace is perfect because His mind perfectly stays on thee.
How do we keep our mind stayed on God? Trust. Trust means to be confident and sure that there awaits a strong city, walled in with salvation whose gates are open for the righteous. Trust places itself in the One who preserves the strong city in eternity, reasoning that , “Oh, God! If you can preserve the strong city until the day of your second coming, surely you can preserve me now in this hard circumstance.”
Application
How do we take these truths and apply them to our lives? Verse 1 says, “In that day shall this song be sung.” Literally, we should sing the promises of God. When your daughter has a seizure and you have to rush her to the hospital, sing the psalter the whole drive. When your boss is domineering and overbearing, sing the psalter all work day long. When your children disobey, sing the psalter over them, around them, and with them. When you feel like you do not have peace, sing the song of Isaiah 26 to remind yourself that you have a God who keeps you in perfect peace both now in Babylon and forever in the strong city.
Conclusion
Today, we have seen that there waits for us a strong city. Salvation hems her citizens within the city. Her gates are open to the righteous and those who keep the faith. And lastly, peace characterizes the citizens of this city. I ask you church, who provided your salvation? Who imputed his righteousness unto you? Who gave you the gift of faith? Well, the answer is none other than the Prince of Peace, Jesus Christ. We should walk away from this portion of Isaiah, not only singing the promises, but worshiping Jesus in our hearts who is the basis for our perfect peace. To hold the promises of Isaiah 26 in our heart is to hold onto the perfect work of Jesus Christ. Tonight, I ask, do you know Christ as Savior and Lord? When you die, will you be a member of that strong city? Or will you be on the outside of the walls of salvation like those who stood outside of the Ark in the days of Noah? Will the gates be shut to you? Are you void of peace? If so, I implore you to seek Christ in salvation for forgiveness of your sins. Come to him for faith, asking for repentance, a new heart, new motives, new love . . . that you would be a recipient of perfect peace from a perfect Savior.
