The Salt of the Earth and the Light of the World

“You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot. “You are the light of the world. A town built on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven.” (Mt 5:13-16)
 
Introduction
Two weeks ago, we finished the 8 Beatitudes. And I want us to discuss some more teachings written in Matthew 5-7.
 
In these chapters, Matthew collected some teachings Jesus taught on a mountainside, which is called “the Sermon on the Mount.” The 8 beatitudes are also part of this.
 
After teaching the 8 blessings, Jesus started to teach His disciples how they should behave in the world using two metaphors—salt and light. Jesus said, “You are the salt of the earth…” and “You are the light of the world.”
 
We need to think about why Jesus used these two metaphors to describe His followers. We might ask questions like, “what are some aspects of salt and light that Jesus compared His disciples to?” and “what does it mean to live as the salt of the earth and the light of the world and what would it look like?” These are the questions I want us to think about through today’s sermon.
 
The Salt of the Earth
So, let’s first think about the metaphor of salt. Even though this metaphor is used less often in the Bible compared to light, we can find some passages where salt is used.
 
1) The Purifying Aspect of Salt
First, salt is a symbol of purity. So, it was often used in sacrifices.
 
For example, when God was teaching the Israelites how to make a fragrant blend of holy incense for the holy place, He said,  “It is to be salted and pure and sacred” (Ex 30:35). Salt has nothing to do with fragrance, but still the incense was to be salted because it symbolizes its holiness, purity, and sacredness.
 
We find another case in the Bible where salt is used to purify. God said to the prophet Ezekiel about the birth of Israel, “On the day you were born your cord was not cut, nor were you washed with water to make you clean, nor were you rubbed with salt or wrapped in cloths” (Ezk 16:4)
 
Here, we can understand some of the actions such as cutting a baby’s cord, washing them with water, and wrapping them in clothes. But why were babies rubbed with salt?
 
From this verse, we can infer that it was an ancient custom to rub newborn babies with salt. It’s likely that they did it to purify the babies.
 
We also read an example of salt being used to purify sin. 2Kg 2:19-22 says,
 
“The people of the city said to Elisha, “Look, our lord, this town is well situated, as you can see, but the water is bad and the land is unproductive.” “Bring me a new bowl,” he said, “and put salt in it.” So they brought it to him. Then he went out to the spring and threw the salt into it, saying, “This is what the Lord says: ‘I have healed this water. Never again will it cause death or make the land unproductive.’” And the water has remained pure to this day, according to the word Elisha had spoken.” (2Kg 2:19-22)
 
This is what happened right after the prophet Elisha took over the prophetic ministry of Elijah. In this passage, the city refers to Jericho. Even though it was located in a good place, the land wasn’t productive because the water was bad.
 
It was certainly the result of rebuilding the city. After conquering Jericho, Joshua pronounced an oath, saying,  “Cursed before the Lord is the one who undertakes to rebuild this city, Jericho: “At the cost of his firstborn son he will lay its foundations; at the cost of his youngest he will set up its gates.” (Jos 6:26)
 
However, Jericho was rebuilt when Ahab was king of the northern kingdom of Israel. 1 Kg 16:34 says, “In Ahab’s time, Hiel of Bethel rebuilt Jericho. He laid its foundations at the cost of his firstborn son Abiram, and he set up its gates at the cost of his youngest son Segub, in accordance with the word of the Lord spoken by Joshua son of Nun” (1Kg 16:34)
 
So, it’s likely that the water in Jericho was also cursed as a result of rebuilding the city. So, when Elisha stayed in Jericho, the people of the city came to him to ask him to do something about the water.
 
Then Elisha ordered them to bring a new bowl with salt in it. And when he threw the salt into the spring in Jericho, the water was healed and recovered its productive capacity.
 
So, salt was used in the Old Testament for purification. But that’s not the only thing that salt represents.
 
2) The Unchanging Nature of Salt
Salt is often used to preserve food because it prevents spoilage. So, salt is also used in the Bible to show the unchanging nature of God’s covenant. God said to Moses, 
 
“Whatever is set aside from the holy offerings the Israelites present to the Lord I give to you and your sons and daughters as your perpetual share. It is an everlasting covenant of salt before the Lord for both you and your offspring.” (Nm 18:19)
 
Here, the everlasting aspect of God’s covenant is reinforced by the metaphor of salt. Just as salt doesn’t change, God’s covenant never changes.
 
So, according to these passages about salt in the Old Testament, the fact that Christ’s followers are the salt of the earth means that we are called to purify the world tainted by sin and prevent the world from decaying. In order to equip us for this job, God has given us His word along with His promises and covenant and Jesus has given us the gospel.
 
3) Salt Gives Flavor
However, there’s one more important aspect of salt. Salt not only purifies and preserves, but it also gives flavor. Giving flavor is more beneficial than preventing decay when it comes to the roles of salt. In fact, that’s the most important characteristic of salt.
 
There are many kinds of ingredients that give certain flavors to food, but saltiness is only obtained by salt. Nothing can make food salty except for salt, which is essential in cooking.
 
I like to cook so I enjoy making different kinds of food, mainly Korean food, and I use different kinds of ingredients according to the kind of food I make. But there’s one thing that I always use without exception, which is salt. I can’t even imagine making food without salt. I don’t use it a lot, but even a small amount of salt plays a significant role in giving flavor to food.
 
That’s the purpose of Jesus coming into the world. He didn’t come to this world just to prevent it from decaying. The main purpose of His incarnation, death, and resurrection is to save the world and allow human beings to have abundant life in Him. As Jesus said, 
 
“I have come that they may have life, and have it to the full.” (Jn 10:10)
 
Just as a small amount of salt gives amazing flavor to a whole dish, and just as a kernel of wheat falls to the ground and dies to produce many seeds, Jesus came to the world and laid down His life on the cross to give us more abundant and blessed life. We find true purpose and happiness in life in Jesus. And as Christians, we’re to follow His example by laying down our lives for others.
 
We need to remember that Christians are in the world, but not of the world. We live in the world, but we don’t belong to it. If Christians are completely separated from the world, who would go into the world tainted by sin to make it pure again with the gospel of Jesus Christ? So, we must go into the world.
 
But as we’re living in the world, we must be very careful not to lose our identity as the salt of the earth. As Jesus said, “If the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot” (Mt 5:13)
 
Technically speaking, salt can’t lose its saltiness because NaCl, sodium chloride, is a perfect compound. Nevertheless, Jesus still warns us of the possibility of salt losing its saltiness because that can easily happen in a Christian’s life.
 
Most of the salt used in Jesus’ time was not obtained by distilling salt water, but extracted from saline swamps, so a lot of impurities were mixed in it. And the more impurities that were mixed in the salt, the less taste there was. People didn’t use such low-quality salt in their food. They just threw it outside.
 
That’s what Jesus warns will happen when we lose saltiness as the salt of the earth. If we lose our identities as Jesus’ disciples and if our lives are mixed with impurities such as worries, temptations, and desires of the world, we’ll lose our saltiness and identities as Christians and no longer carry out the mission God has given us in Christ.
 
Rather than purifying the world, we will be affected by the corruption of the world. Rather than preserving the world from decay, we’ll find ourselves becoming rotten. And, rather than giving good flavor in the world, we’ll end up being thrown out and trampled. That’s what will happen if we lose our saltiness.
 
So as the salt of the earth, we should make every effort not to lose the precious identities Jesus has given us by continuing to try to remain in Jesus, keep ourselves from worldly things, and renew our minds through God’s word rather than conform to the pattern of this world. That’s the fight of faith that we should continue to fight as Jesus’ followers.
 
Rather than following the ways of the world, we should follow God’s word so that we may serve as preservatives in the world where there’s no absolute moral standard. And by following the example of Jesus’ life, we are to be able to present the true meaning of blessed life so that others around us can also find true happiness and purpose of life in Jesus Christ and live a new and abundant life in Him. I believe that’s what it means to serve as the salt of the earth.
 
The Light of the World
Now, let’s think about the metaphor of light. The metaphor of light is used often in the Bible. Light refers to God Himself since 1 John 1:5 says, “God is light; in him there is no darkness at all.” (1 Jn 1:5)
 
Light was what God first created. Before God created light on the first day, the world was formless, empty, and filled with darkness. But God’s light drove out darkness and everything was put in order in the light.
 
The Bible also says that Jesus, the Son of God, came to the world as the light of the world.
 
John 1:4-5 says, “In him was life, and that life was the light of all mankind. The light shines in the darkness…” (Jn 1:4-5)
 
Just as God first shined His light in the world filled with darkness, Jesus came to the world as the light of the world and shined his light on us.
 
Before the light of Jesus shined in our lives, we lived a chaotic, empty, and dark life like the world before creation. But, when we were empty, lonely, and lost in darkness, ℗ “God, who said, “Let light shine out of darkness,” made his light shine in our hearts to give us the light of the knowledge of God’s glory displayed in the face of Christ” (2Co 4:6).
 
Now, in Jesus Christ we no longer live in darkness because “He has rescued us from the dominion of darkness and brought us into the kingdom of the Son he loves” (Col 1:13).
 
These are what light mainly refers to in the Bible. It refers to God, His creation, and Jesus Christ. However, it doesn’t end there because Jesus said that we’re also the light of the world.
 
Before God shined His light on us through Jesus Christ, we not only lived in darkness but we ourselves were darkness. But Jesus drove out the darkness in our hearts with His light and filled them with His light of life instead. Now, Jesus no longer sees us as darkness, but light because of the light He has given us.
 
The apostle Paul did a great job describing this truth. He said, “you were once darkness, but now you are light in the Lord. Live as children of light” (Eph 5:8)
 
Now, as the light of the world, we need to learn how to shine the light of Jesus to those around us through our lives. Just like how Jesus’ light shined on us in darkness, we should also light the world by testifying to His light of life through our words and actions.
 
In this sense, what Jesus taught on the mount gives us some important insights about what it means for us to become the light of the world.
 
When Jesus compared His followers to the light of the world, He explained three aspects of light.
 
First, it’s not concealable. Jesus said, “You are the light of the world. A town built on a hill cannot be hidden.” (Mt 5:14).
 
There is nothing clearer than light in the darkness. We can even see a little candlelight clearly if it is dark. Likewise, if we truly receive Jesus’ light, it can’t be hidden. So, if people around us don’t notice any light from us, we should check if we’re really in the light.
 
Saltiness is sensed by the tongue and light is detected by eyes and both please people. A town on a hill can’t be hidden even in the middle of the night because of its light. Even though we can’t see particles of salt in food, we all know if it’s seasoned with salt or not.
 
Likewise, if we’re really the salt of the earth and the light of the world, those around us must be able to notice the flavor and the light. How we think, how we speak, how we spend our time and money, how we treat others, and how we behave must be different and distinguished.
 
This is possible only when we remain in Jesus and are filled with His light. And if we really live that kind of life, those around us will notice it and be drawn to it. That’s the first step to proclaiming the gospel of Jesus Christ through our lives.
 
Second, the light is for everyone. Jesus continued, “Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house” (Mt 5:15).
 
The reason a lamp is put on its stand, not under a bowl, is to shine the light on as many things and people as possible. The light of Jesus isn’t for a specific group of people. It is for everyone on earth. There’s no discrimination in His light.
 
Then, we’re also to try to approach all kinds of people, including our enemies, not just those whom we want to get along with.
 
Third, the purpose of shining the light is only for the glory of God. Jesus said,

​“In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven” (Mt 5:16).
 
As Christians, we are called to do many good things in the world. But, what’s more important than doing good things is the motivation behind it.
 
If our good deeds do not reflect who God is, or let others see the glory of God, but only build our own reputations, it means nothing. There would be no reward left in heaven for us because we already received our reward here in this world.
 
 That’s because the ultimate purpose of us being the light of the world is not to reveal our goodness but to allow others to see God’s true light through our words and deeds, come to him, and glorify him.
 
Today, we talked about what it means to be the salt of the earth and the light of the world according to Jesus’ sermon on the mount.
 
What makes me sad is when I see Christians losing their saltiness and light. A lot of Christians just exist in the world as salt without saltiness and a lamp without light. We’re called to be the salt of the earth that purifies the world, prevents the world from decaying, and gives good flavor to the world by proclaiming the gospel of Jesus Christ, but it’s hard to find Christians who are respected by non-believers for their lives because they’ve lost their saltiness.
 
We’re called to shine the light of Jesus on the world through our words and actions so that those around us can experience God’s goodness and love and return to Him, glorifying Him, but our light is so hidden that no one even notices that we’re Christians. That’s not the kind of life we’re called to live.
 
Now, I want us to look back on our lives and return to God, repenting of our past wrong decisions and failures. I hope and pray that we can all recover the saltiness and bright light that God has allowed us to have in Christ by going back to Jesus and remaining in Him so that we can truly serve as the salt of the earth and the light of the world, following Jesus’ way.
 
Let’s pray.
 
[Closing prayer]
Heavenly Father, thank You for letting us know what kind of beings we’ve become in Christ through Your grace. Thank You for calling us to be Your salt and light in the world.
 
We humbly confess that we’ve failed many times to live according to Your calling. Rather than shining Your light in the world, we’ve often assimilated to the world. We’ve lost our saltiness and light.
 
Now Lord, we want to recover the precious identities You’ve given us. We want to stand up and live for You and Your glory again. But we can’t do it alone. So we humbly lay down our thoughts and wills and invite You. Please come and fill us with Your light of life so that we can really live as Your salt and light wherever we are.
 
Let us be filled with Your presence and give thanks to You in all circumstances so that Your goodness, faithfulness, and love may be revealed through our lives. We pray that only Your name be glorified through our words and actions.
 
In Jesus’ precious name we pray. Amen.
 
[Reflection Questions]
1. What do you think are some reasons that Christians lose their saltiness and light nowadays?
 
2. What do you think it means for you to be the salt and the light of the world? What do you think are some ways you can live in accordance with this calling?