God’s Word Fulfills Its Purpose -- Sermon for Pentecost 7A (Isaiah 55; Matthew 13)

Isaiah 55:10-13; Matthew 13:1-9, 18-23

Every spring I sow grass seed to fix the barren spots in the lawn. Sometimes the seed does its job and grass appears where it’s supposed to appear; but not always. Some of that seed falls on ground that doesn’t want to produce any new grass, no matter what I do to the soil. Then there’s the grass that makes a home in unintended spots, like in the middle of my flower garden. I don’t know if it’s the seeds or the soil, but either one seems to have a mind of its own.

In our Gospel reading this morning from Matthew 13, we encounter Jesus sitting in a boat anchored on the Sea of Galilee because a large crowd gathered to hear him teach. This chapter offers us several well-known parables, some of which Pastor Dan is going to explore, along with Matthew’s explanation of why Jesus used parables in his teaching about the kingdom of God. While we often think Jesus used parables to illustrate his sermons because the people could better understand his message, according to Matthew, it’s a bit more complicated than that. That’s because not everyone gets the message. It all depends on the soil of a person’s heart, or at least that’s what the first parable seems to suggest. 

Our reading from Matthew 13 is divided into two parts. Part One is the famous parable, while Part Two offers us an allegorical interpretation of that parable. In the verses that lie between these two parts of our reading, Jesus told the disciples that they were given the privilege of understanding the secrets of the kingdom of God, unlike those who failed to understand his message. But even the disciples needed an interpretation of the parable. According to Jesus’ explanation, when it comes to understanding the message of the kingdom, it all depends on the soil on which the seed lands.  

The Lectionary pairs the Parable of the Sower with a reading from Isaiah 55, in which the prophet tells a group of exiles living in Babylon that God’s word will not return empty. While the Parable of the Sower focuses on the coming of God’s reign in our midst, the prophet’s message speaks of God’s covenant with Israel. The prophet that scholars call Second Isaiah wants the people living in exile to know that God’s word or promise will fulfill its purpose. Because God stays true to the covenant promise, no matter what the people do, God’s people can join the mountains and the hills in bursting in songs of praise, while the trees of the field clap their hands. 

I love Isaiah’s description of the mountains, hills, and trees joining together to offer praise to God. If you spend any time in the mountains or among the trees, you can understand how powerful this image is. When I read this passage, my mind goes to my years growing up in the shadow of Mount Shasta, a massive fourteen-thousand-foot volcano. If you’ve ever spent time near Mount Shasta, you will recognize that it does have a certain aura about it that sings about the grandeur of creation, especially when it’s covered with snow. Or think of great stands of trees, such as the Sequoias.  The Sequoias are massive, and some are quite ancient. So, I can, using my imagination, envision them clapping their hands in joy as the wind blows through their branches. 

So, as the theme song from the Sound of Music puts it:

The hills are alive with the sound of music;

With songs they have sung for a thousand years.

The hills fill my heart with the sound of music.

My heart wants to sing ev'ry song it hears.

Or, as the prophet we know as Second Isaiah declares to a group of exiles: 

“For you shall go out in joy and be led back in peace; the mountains and the hills before you shall burst into song, and all the trees of the field shall clap their hands” (Is. 55: 12). 

Why should we join the mountains, hills, and trees in giving praise to God? According to Second Isaiah, we do this because God is always faithful to God’s covenant promises. The question is whether our hearts are ready to embrace this promise.

This is where Jesus’ parable comes into play. The question Jesus asks us to consider in this parable is whether we are ready to believe that God will be faithful to the promise to bring into existence God’s kingdom. According to Jesus, there are lots of reasons why we fail to respond positively. It might be that we’re too distracted by the things of this life to pay attention to what God is doing in our midst, or we might simply want to do our own thing, so we close our ears to Jesus’ message. While it might seem like there are too many obstacles for God’s reign to break into our world, Second Isaiah reminds us that God’s word will not return void. 

Now there were good reasons why the people living in exile in Babylon might question the prophet’s message. It’s likely that the prophet offered his message to people who had lost all hope that they and their descendants would ever return home. Despite their seemingly hopeless situation, the prophet tells the people to stand firm because God will not forget the covenant made with the people, beginning with Abraham and then through Moses. Therefore, he tells them that they can put their trust in God because God’s word will accomplish its purpose. Since God’s promises will not return empty, these exiles can join with the mountains, the hills, and the trees in making a joyful noise before the LORD. 

The reading from Isaiah 55 begins with the word “for,” which suggests that this word builds off of a previous word. That word is found in verse six, which declares: “Seek the LORD while He can be found, call to Him while He is near” (Is. 55:6  Tanakh). In other words, the prophet invites the people to prepare themselves to receive a word from God concerning the covenant. So, the prophet tells us that God’s word comes to the people like a seed that God waters with rain and snow from the heavens. After it sprouts, it brings forth seed that can be sown, so that the people can bake bread that will sustain them as they wait for their deliverance.

This brings us back to our Gospel reading from Matthew 13, where Jesus suggests that the sower casts seed indiscriminately. Because the seed lands on different kinds of soil, sometimes it bears fruit, and at other times it doesn’t. While Isaiah uses a similar image, he envisions a different outcome. That’s because Isaiah believes that when God sows the Word, it fulfills its purpose.

While the two visions of seed being sown may sound contradictory, perhaps both can be true. The Word can fall on deaf ears and closed hearts, which, for a time, can hinder God’s purpose. However, because God always remains faithful to the covenant promise, which is everlasting, in the end the promise of God’s kingdom will come to fruition. Ultimately, following Paul’s message in 2 Corinthians 5, this will lead to the reconciliation of all things to God in Christ (2 Cor. 5:16-20). Therefore, as Isaiah declares in verse three of chapter 55: 

Incline your ear and come to me; hearken, and you shall be revived. And I will make with you an everlasting covenant, the enduring loyalty promised to David (Is. 55:3 Tanakh).

Although our situation is very different from that of the Babylonian exiles, sometimes we can feel like exiles, unsure about our futures. Maybe you are feeling estranged from what is going on in the world. While we recently celebrated the nation’s 250th birthday, the divisions and the coarseness of society have tempered the enthusiasm of many. Nevertheless, no matter what is going on in the world, Isaiah wants us to know that God’s covenant promise stands true no matter what is happening around us. Both Isaiah and Jesus invite us to put our trust in God, believing that God will fulfill the promise embedded in God’s covenants, whether it’s through Abraham, Moses, or Jesus. As Jeremiah reminds us, God will make a new covenant written not on stone but on hearts, so that we will all know the LORD (Jer. 31:31-34).

Isaiah looks back to God’s covenant with David (Is. 55:3), which makes sense, in context, since there was hope that God would restore the house of David to the throne of Judah. But, perhaps we might go back to an earlier covenant, the one God made with Abraham and Sarah. In Genesis 17, God told Abraham that the covenant God was making with him and his descendants would be an everlasting one (Gen. 17:1-7). This covenant is rooted in Abraham’s calling to head out on a journey of faith that would lead the family to Canaan. If Abraham and Sarah embraced this call, then God would make them a great nation and that through their descendants the nations of the earth would be blessed (Gen. 12:1-3). I believe that through faith in Jesus, God adopts us into that family, so we can participate in this calling.  

We share in this everlasting promise made first to the Jewish people through an act of adoption. Therefore, as Paul states, through the Spirit of God we can call out “Abba! Father!” And, because we are children of God, we are heirs of the promise  (Rom. 8:14-17). So let us go out with joy and be led back in peace. May we join the mountains and the hills in their song of praise. Let us join the trees of the field in clapping our hands. May we embrace the cypress and the myrtle trees, which serve as a memorial to God, reminding God and us that the covenant will not be cut off and that it will lead to the blessing of the nations. 

Preached by:

Dr. Robert D. Cornwall

Pulpit Supply

First Presbyterian Church (USA)

Troy, Michigan

July 12, 2026

Pentecost 7A