Salt and Light

Matthew 5:13-16
P.G. Mathew | Sunday, May 04, 1997
Copyright © 1997, P.G. Mathew

In the first twelve verses of Matthew 5 in Jesus’ Sermon on the Mount we find the beatitudes. These blessings–“Blessed are the poor in spirit. . .” “Blessed are those who mourn. . .” “Blessed are the meek. . .” “Blessed are those who hunger and thirst after righteousness,” and so on–are descriptions of the character that Christians must have. But from verse 13 on, we are told how we must function in the world as the church of Jesus Christ. In this section, Matthew 5:13-16, Jesus tells his disciples, “You are the salt of the earth” and “You are the light of the world.” In this study, therefore, we will examine what it means to be salt and light.

The Rotten World

Among the civilized people of the world in the latter part of the nineteenth century there was a great sense of optimism which was fueled by evolutionary ideas. These people expected that in the near future wars would be abolished, diseases would be wiped out, suffering would be eliminated, and discrimination would cease. They fully expected that in the twentieth century they would see one loving, global society whose citizens would become progressively enlightened as knowledge increased. Yet, despite the optimism, the twentieth century has become the bloodiest of all centuries. People have not improved in their nature and behavior despite enormous increases of knowledge in almost every sphere.

When Jesus spoke on the mountain to a bunch of insignificant and unlearned men of Galilee, telling them, “You are the salt of the earth,” he was saying that the world was rotten and rotting like rotting meat. Isn’t this still true today? The people of this world are wicked, sinful, and against God. They glory in their shame and even today many are coming out proudly declaring their lesbianism, homosexuality and other deviant lifestyles. Evil has become good and good has become evil.

This has been the situation in the world since the fall of man. Why? Because of the sin of human hearts. In Jeremiah 17:9 we read, “The heart is deceitful above all things and beyond cure,” and in Matthew 15:19 Jesus said, “For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false testimony, slander,” and so on. In Romans 1:21, 24 and 26 we read, “Although they knew God, they neither glorified him as God nor gave thanks to him. . . God gave them over [in judgment] to the sinful desires of their heart to sexual impurity for the degrading of their bodies with one another. . . God gave them over to shameful lusts.” And in Romans 1:28 we read that God “gave them over to a depraved mind to do what ought not to be done.”

If you continue to read in Romans 1, in verses 29 through 32 you will see the assessment of Jesus Christ that the world is rotten and rotting; therefore, his statement that Christians must function as the salt of the earth is also still true. “They have become filled with every kind of wickedness, evil, greed and depravity. They are full of envy, murder, strife, deceit and malice. They are gossips, slanderers, God-haters, insolent, arrogant and boastful; they invent ways of doing evil; they disobey their parents; they are senseless, faithless, heartless, ruthless. Although they know God’s righteous decree that those who do such things deserve death, they not only continue to do these very things but also approve of those who practice them.”

Salt for the World

In verse 13 we read, “You are the salt of the earth,” and in the Greek it is “You and you alone are the salt of the earth. Why did Jesus say that to this small group of uneducated, poor, humble, Galilean disciples? He was telling them that although the world of men is rotting, they as Christians were to function like salt in the world. Why? They alone were different from the world. Like the world, they had also been dead, but from their depravity and spiritual death they had been delivered by the power of God and made alive by their relationship with Christ.

This is true of all Christians. In Ephesians 2:3-4 we read, “Like the rest, we were by nature objects of wrath. But because of his great love for us, God, who is rich in mercy, made us alive with Christ even when we were dead in transgressions. . .” And in 2 Corinthians 5:17 we read, “Therefore, if anyone is in Christ, he is a new creation; the old has gone, the new has come!”

All Christians, then, are the salt of the earth. Why? We have been given new birth and a new nature–the divine nature–through union with Christ. Therefore, we must also live for the benefit of this rotting and rotten world.

The Distinctiveness of Salt

In this short statement Jesus was also warning his disciples to avoid two errors. First, he was saying that Christians must not forsake the world and go into monasteries. Why? Salt will do no good to meat unless it is rubbed into it. Only then will it function as an antiseptic. We are to be in the world so that the world may benefit by our difference from the world. And second, he was saying that Christians must also avoid the error of being one with the world and embracing its values and ways.

These warnings are applicable to us today. I have seen many modern evangelicals discovering materialism all of a sudden. In fact, many preachers are preaching that rather than looking forward to a heaven “paved with gold,” they want some gold and goodies and symbols of luxury now. But when they say these things, what are they doing? Denying the distinctiveness of the salt of the earth.

I recently visited China and talked with university professors there. They were all atheists interested in American values. They all want to be materialistic and are working very hard to be exactly like the Americans. Today’s church is doing the same thing by trying to be like the world in its value and fashion. But that is an error, because the ways of the world are evil. We must be as different as salt is different from dead meat. We must be different from the rotting world. We must be in the world but not of the world. Why? So that the world may be helped by us. We must be different and must glory in our difference.

When Jesus said, “You alone are the salt of the earth,” this was a high compliment and great encouragement from the lips of the Sovereign Lord of the universe. This statement gives every Christian great dignity and self-esteem. Thus, I feel sorry for you if you are trying to be like the world in speech, in dress, in value, and in fashion. By trying to conform to the pattern of the world, you are declaring that you are darkness, that you are rotting and that you are not a Christian.

The Purpose of Salt

Jesus did not tell his disciples, “You are the sugar of the world,” but “You are the salt.” Let us, then, examine what the purpose of salt is and how Christians function as salt.

First, salt functions as a preservative. It is an antiseptic which performs the negative function of preventing spoiling meat from becoming even more rotten and corrupt. In tropical countries where there is no refrigeration, people rub salt into meat to keep it from going bad. In the same way, when Christians come in close contact with the sinful people of the world, the world is kept from progressing further into unspeakable foulness. Christians benefit secular society. Without their presence, the world would degenerate at an even faster rate. As a moral antiseptic, Christians keep the corruption of society at bay by opposing moral decay by their lives and their words.

Now we must realize that, like salt, Christians might irritate the wound at first. Remember, Christians are not sugar; they are salt. But I say, welcome the irritation that Christians bring about. Welcome the discomfort that the salt of the earth initially creates, because salt will greatly benefit you.

Second, salt is necessary for flavor. Without Christians and the gospel they proclaim and practice, this world would be more insipid. There is no true flavor found in the world. There is no true joy found in this world. Only the company of Christians gives flavor and joy to the world. We can prove this by examining the worldly parties and good times. What are they like? Boring, tasteless, and insipid. As Christians, we have the function to provide flavor and taste to the world. The gospel of Jesus Christ is the power of God unto salvation to everyone who believes. The world is without hope, and only the Christian, by his proclamation and practice, will point the world to hope in Jesus Christ.

Third, salt is white, symbolizing purity. Christians are to be in the world and yet live pure, different lives. As I said before, Christians should glory in their difference. They are citizens of heaven who are living in this rotting world for its benefit. As such, they must constantly resist the temptation of being like the world and must be like the Lord Jesus Christ. They must oppose the rotting and foul values of the world, and proclaim and practice biblical lifestyles. As we read in James 4:4, “Friendship [or conformity] with the world is hatred toward God.” As the salt of the earth, we must be holy, pure and different from the world. In Romans 12:2 Paul says, “Do not conform any longer to the pattern of this world” and in James 1:27 we read that we must keep ourselves “from being polluted by the world.” In 1 Peter 4:4 we read that the world thinks it strange “that you do not plunge with them into the same flood of dissipation.” Salt is pure.

Fourth, salt also was used as a fertilizer. Christians must function in a way that promotes the growth of that which is good in the world. They must oppose evil and promote good. In God’s common grace, there is much good in his world, and Christians must support and promote that which is useful to mankind. For example, Christians must engage in political life to promote policies that are helpful to families. Historically, Christians have championed many causes that promoted the good of humanity. They have suppressed evil and caused good to grow and flourish.

Fifth, salt causes people to become thirsty. In the same way, Christians should cause people to thirst for Jesus Christ and his gospel. If we live as Christians daily for God’s glory alone in the midst of the world, the world will observe us and desire to know about Jesus Christ. Now, I don’t mean all the people of the world will do this, but God’s elect will. Through us God will generate within them a thirst for the living God, and they will come to us and ask, “Why are you different? Why are you so full of hope and peace and joy even in the midst of troubles?” When they do this, you then can tell them about Jesus Christ.

So we must ask ourselves: Are we functioning as salt in our society? Are we causing people to thirst for Jesus Christ? In John 7:37, Jesus declared at the Feast, “If anyone is thirsty, let him come to me and drink.” It is the church’s business to produce in the hearts of unbelievers great thirst for Jesus Christ.

Worldliness Destroys Saltiness

Then Jesus said that if salt lost its saltiness, it would become useless and worthless. Can people lose their saltiness? Yes. How? Through worldliness. When we conform to the pattern of the world, when we embrace the rotten values of the world, when we become materialistic, sensual and pleasure-seeking, we lose our saltiness. We become like the world–rotting, rotten, and foul.

We must realize that we are to be in the world but not of the world. Although we are in the world, we must focus on Jesus Christ and his teachings. We are to be different, and if we are not, we will become fools. We will become useless to God, useless to our families, useless to society–yea, useless to the world. And the day will come when saltless professors of Christ will be cast out by the Lord Jesus Christ.

We read about this in Matthew 8:11-12: “I say to you that many will come from the east and the west, and will take their places at the feast with Abraham, Isaac and Jacob in the kingdom of heaven. But the subjects of the kingdom will be thrown outside, into the darkness. where there will be weeping and gnashing of teeth.” And in 2 Timothy 4:10 Paul, with great grief, speaks about his fellow worker Demas, “Demas, because he loved this world, has deserted me and has gone to Thessalonica.”

Yes, one day the Lord Jesus Christ will say to such people, “Depart from me, I never knew you.” One day he will speak to them, “Depart from me, you who are cursed, into the eternal fire prepared for the devil and his angels.” That day is coming!

The Light of the Dark World

Christians, then, are the salt of the earth and they should benefit the earth while they live in it. Then Jesus also told his disciples, “You are the light of the world.” In the Greek text it is, “You and you alone are the light of the world.”

What is light? In the fifteenth and sixteenth centuries, many ancient Greek writings were discovered, and that period was called the Renaissance, meaning a rebirth. In the eighteenth century, people gloried in jettisoning revelation, meaning God and his authority. Then they enthroned reason–the fallen reason of man. What did they call this period of rationalism? The Enlightenment. Was this really enlightenment? No. It was an age of darkness.

Here we see Jesus Christ on a mountain speaking to a bunch of poor, humble, stinking fisherman. What is he telling them? “You and you alone are the light of the world.” What a great compliment this was! What great dignity God bestowed upon them! And this is true of you, if you are a Christian. If you trust in Jesus Christ alone for your salvation, you alone are the salt of the earth and the light of the world.

Who is the light of the world? Christians. Jesus was not saying that light is found in Aristotle, Socrates, Plato, emperors, politicians, philosophers, plutocrats, technocrats, artists, or scientists. No. The poor, humble Galileans who trusted in Jesus Christ and confessed that he is the Christ, the Son of the living God–and all true Christians throughout history–are alone the light of the world.

What about all the books written by the wise people of the world? Let me tell you, they are darkness. Their authors are darkness just as the world is darkness. That is the implication of the statement that “You and you alone are the light of the world.”

In Proverbs 4:19 we read, “The way of the wicked is like deep darkness.” Oh, all the wisdom of the world may be couched in high philosophical terms, but what does it really consist of? Deep darkness.

God Gives Light

In Ephesians 5:8,9 Paul says, “For you were once darkness but now you are light in the Lord. Live as children of light.” These humble, poor, despised Galileans were once darkness, but then they saw a great light–Jesus–and were made able to be light in the Lord. In 2 Corinthians 4:4-6 Paul writes, “The god of this age has blinded the minds of unbelievers so that they cannot see the light of the gospel of glory of Christ, who is the image of God. . . . [But] 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 the glory of God in the face of Christ.”

We were once darkness, but now we are light in the Lord. How are we supposed to live? As children of the light. Jesus said he was the light of the world and then he told his disciples that they are the light of the world. In other words, the world is deep darkness–this world of professors, politicians, scientists, technocrats, plutocrats, movie stars, and religious gurus. But in this world of deep darkness, God planted his church as light.

Now, do you understand the absurdity of Christians wanting to become like the world? It is absolute foolishness! Should we tell lies because the world lies? By no means! As I said before, Christians are not to retreat from the world into monasteries, but neither are we to seek to become like the world by following its fashions and darkness. (PGM) We must be in the world and function as its light as we proclaim and practice the gospel of Jesus Christ. We must realize that although the world is sinful and dark, God loves it and sent his one and only Son to redeem it.

In John 3:19-21 Jesus said, “This is the verdict: Light has come into the world, but men loved darkness instead of light because their deeds were evil. Everyone who does evil hates the light, and will not come into the light for fear that his deeds will be exposed. But whoever lives by the truth comes into the light so that it may be seen plainly that what he has done has been done through God.”

So God loves the world, and he sent his Son to be its light. He has purposed to save a people from their sins, and he will save them. He saves them through the church as Christians proclaim and demonstrate the gospel in every aspect of life. Whether in the workplace or the marketplace, whether in the political sphere, the family, or the school, as we demonstrate the light of Christianity, God will save some out of darkness just as he saved us.

Light Must Be Different

Why, then, are Christians placed in the world? They are to benefit the world. But we benefit it only when we live as light. If the people of the world fornicate and we fornicate, what is the difference? If they lie and we lie, what is the difference? When they do a sloppy job, and we do a sloppy job, what is the difference? When they complain and murmur against their bosses, and we complain and murmur against our bosses, what is the difference? When they don’t love their spouses, and we don’t love our spouses, what is the difference? When they divorce and we divorce, what is the difference? When they are lazy and we are lazy, what is the difference?

We cannot benefit the world when we are like the world. Christians are to reflect the light of Jesus to the world. And what is this light? It is the light of salvation, the light of eternal life, the light of the knowledge of God, the light of the joy of salvation, the light of hope, and the light that shines in darkness. It is the light that opens the eyes of the blind and causes them to see the light of the glory of God in the face of Jesus Christ.

Our mission is to be light to the world. When the Lord Jesus Christ commissioned the apostle Paul, he told him, “I am sending you to [the Gentiles] to open their eyes and turn them from darkness to light, and from the power of Satan to God” (Acts 26:17-18). And Peter tells us in 1 Peter 2:9, “You are a chosen people, a royal priesthood, a holy nation, a people belonging to God, that you may declare the praises of him who called you out of darkness into his wonderful light.”

Shining Is Not Optional

Just as salt is known for its saltiness, light is known for its shining, and this shining is not optional. If we are Christians, shining is our business–our only business–in the world.

In 2 Corinthians 2:14-16 Paul spoke about his life as an apostle: “But thanks be to God, who always leads us in triumphal procession in Christ and through us spreads everywhere the fragrance of the knowledge of him.” Notice, Paul says, “through us,” meaning it is not through angels but through the church–through Christians, through the apostles, through those who Jesus said are the salt of the earth and the light of the world–that the knowledge of Christ comes to the world. Paul continues, “For we are to God the aroma of Christ among those who are being saved and those who are perishing. To the one we are the smell of death; to the other, the fragrance of life.” Have you seen the truth of that in your own life? Many will not come to the light because their deeds are evil, but some will come to the light through us. And Paul concludes, “And who is equal to such a task?” Through us spreads everywhere the fragrance of the knowledge of him.

What is eternal life? Jesus said, “they may know you, the only true God, and Jesus Christ, whom you have sent” (John 17:3). Through us the gospel knowledge spreads like fragrance in the world. To some it is death, but, praise be to God, to others–to the elect and chosen of God–it is life. What a high purpose God has granted to us!

The Function of Light

How do we function as light? First, we expose the reality of evil. The way of the wicked is deep darkness and they are stumbling, but they do not know why. They are confused and have no understanding of reality. But in Ephesians 5:13 we read, “Everything exposed by the light becomes visible, for it is light that makes everything visible.”

Jesus as the Light of the world exposed the rottenness of the world. The Bible as the light also exposes the sinfulness of this world. The Bible says, “Your word is a lamp to my feet and a light to my path” (Psalm 119:105). What people value and hold dear is exposed as evil by the light of the gospel. This is reality. It is Jesus who declared that the world is in darkness and that man is basically not good but evil. So the evil of the world is exposed by the light of the gospel of Jesus Christ.

The contemporaries of Jesus Christ did not like this exposure. They tried to get rid of the light by crucifying Jesus Christ. Yet, even though they killed him, they failed to extinguish the light. Why? Because Jesus Christ birthed a church, and this true church is the light of the world.

Jesus loves the world that crucified him and he will save his people out of it through the light of his church. Yes, he will convict the world of sin and demand that sinners repent. But let me assure you, just as light will expose evil, it will also expose God and his Christ, the Savior of the world.

Light Enlightens

This light not only exposes the reality of evil, but it also enlightens us to God. The Light of the world opens the eyes of the blind. He who said, “Let light shine out of darkness” when he created the heavens and the earth now speaks in his new creative work, saying, “Let their light into the depths of our hearts,” and there is light. People’s eyes are opened and suddenly the blind sees. And what do they see? The light of the knowledge of the glory of God in the face of Jesus Christ.

Light Shows the Way Out

Not only that, this light also shows the enlightened ones the exit, the way out. There is a way out of darkness, death, hell, and hopelessness. What is it? One must repent and believe on the Lord Jesus Christ, who is very God and very man. In 2 Corinthians 5:21 we read, “God made him who had no sin to become sin for us, so that in him we might become the righteousness of God.” Jesus Christ took our sin and guilt upon himself and died on the cross in our behalf. He was buried, but on the third day he was raised according to the Scriptures. We must repent and believe on this Lord Jesus Christ, the one who took our sin upon himself and paid the penalty in our behalf, the one who offers freely his perfect righteousness as the way out.

We see an example of this in Acts 16. When the panic-stricken Philippian jailer cried out, “What must I do to be saved?” what was the answer? Paul told him, “Believe in the Lord Jesus, and you will be saved.” Friend, it is the gospel that exposes reality to you. It is the gospel that enlightens your eyes and shows you the way out. And I assure you, if you repent and believe on the Lord Jesus Christ this minute, you shall be saved.

Many have been brought out of darkness into God’s marvelous light of hope, life, salvation truth. They have been brought from darkness to fellowship with God, who dwells in unapproachable light. He has provided this way out of darkness–a new and living way–in the person of Jesus Christ who declared, “I am the way, the truth and the life.”

Reality in the Light of the Gospel

Additionally, this light explains reality to us. People understand reality in the light of the gospel. When philosophy, psychology, sociology, government, religion and science fail, the gospel explains all realities. From the gospel we understand who God is, who man is, what the world is, what the future is, what heaven is and what hell is. In the light of the gospel there is, finally, meaning. It tells us how to live and how not to live. It tells us what is right and what is wrong. It tells us how to make the right decision. It tells us when to go and when to stop. It functions as the green light, the yellow light, and the red light.

Jesus said that we are that light in this world. As such, we are to proclaim and practice the gospel. Didn’t Jesus tell his disciples to go into all the world (Matthew 28:18-20)? Why did he say that? All the world must be brought to this light. We must go into all the world and preach the gospel so that through us the world might receive the light of the gospel, the light of truth, the light of life, the light of salvation, the light of purpose, the light of meaning, the light of hope, and the light of joy. The world cannot get it in any other way.

So we and we alone are the light of the world. Through us the world must come to know Jesus Christ. So we are told in Matthew 5:16, “In the same way, let your light shine before men.” That is an aorist imperative, meaning a command. It is a command from the Sovereign Lord of the universe.

How to Shine

How do we let our light shine before an unbelieving world? By living a gospel life. That means we live a separated, holy, biblical life. That means we refuse to be worldly. That means we live a Spirit-filled life.

Do you remember the foolish virgins that we read about in Matthew 25? They had lamps but they did not shine in the deep darkness of the midnight. Why? They had no oil. We must be filled with the oil of the Spirit of God. Why? We are commanded to let our light shine before the world. We are planted in this world for the benefit of people who are sinners, and they will be helped only when we shine. Thus, we must make sure to trim our wicks daily through the practice of the beatitudes.

That is why we have beatitudes ahead of us: Blessed are the poor in spirit, blessed are those who mourn, blessed are the merciful, blessed are those who hunger and thirst for righteousness. We must experience a continuing poverty, a continuing mourning, and so on. We must look to the Light–that is, Jesus–daily so that we may daily reflect his light. Why? We are not light in ourselves. We are light in the Lord.

Psalm 34:5 tells us, “Those who look to him are radiant.” And in 2 Corinthians 3:18 we are given the key for shining: “And we, who with unveiled faces all reflect the Lord’s glory are being transformed into his likeness with ever-increasing glory which comes from the Lord, who is the Spirit.” The people of the world are looking to the actors and actresses who just came out of the closet. That is their pattern. But our pattern is the Lord Jesus Christ, the Lord of glory. And as we look to him and reflect him, we are being transformed into the likeness of his glory. From glory to glory he is changing us.

Paul speaks about shining in Philippians 2:14-16: “Do everything without complaining or arguing, so that you may become blameless and pure, children of God without fault in a crooked and depraved generation”–meaning the darkness of the world– “in which you shine like stars in the universe as you hold out the word of life.” The gospel, the word of life, is the light. As we live it and proclaim it and are changed and transformed by it, we will shine as stars in the universe. Simply put, we shine by living a Spirit-filled life.

The Purpose of Living As Salt and Light

What is the purpose of living as salt and light in the world? First, Jesus says, that men may see our good works. As we live in a way pleasing to God, unbelievers in our workplace, our school, and our neighborhood will behold our good works. In Ephesians 2:10 Paul says, “For we are God’s workmanship, created in Christ Jesus to do good works, which God which God prepared in advance for us to do.” Shining consists in doing good works as we are enabled by God. It is doing righteousness, the exact opposite of what the world does, in other words. So the first purpose is that the unbelieving world may see something that is different.

What is the second and final purpose? Is it that the world may glorify us? No, Jesus said that the world may “praise your Father in heaven.” In Matthew 6:1, 5 and 16 we read of the Pharisees, who did everything before men. What was their goal? That they could be glorified by men. But here the purpose is that men might glorify our Father in heaven.

When we live for the glory of God, we will always be zealous to see that God alone receives glory. When people compliment us, may we say, “No, to God be the glory! I am just nothing, but God enabled me to do this thing. To him alone be the glory!” When we do that, they will join us and glorify God. Such unbelievers may not repent, and yet, the truth is, many of them will be saved. If that happens, then they will truly praise God our heavenly Father. That is the purpose of being the salt of the earth and the light of the world.

Practical Application

In conclusion, let us examine how we can apply this teaching to our lives. First, we must ask ourselves: Are we salt and light? Or are we dead meat and darkness? These are serious questions. And if, after examining ourselves, we find that we are darkness, may we cry out to Jesus Christ that he may save us. Then he will transform us into salt and light.

Second, if we are salt and light, we must be different and glory in our difference.

Third, we must live in the world and yet not be of the world. We must not try to get out of the world. Why? Light is for the dark world and salt is for dead meat.

Fourth, we must be the best we can be with God’s power in our work life, our family life, our school life, our political life and every other aspect of life. We must be the best for Jesus Christ so that we can be winsome and attractive and draw attention to our heavenly Father.

Fifth, we must practice the beatitudes every day, being poor in spirit, mourning over sin, and so on.

Sixth, we must be filled with the oil of the Holy Spirit on a daily basis. We cannot shine without the oil of the Spirit of the living God.

Seventh, we must trim our wicks on a daily basis, meaning we must engage in biblical self-examination.

What will happen when we do these things? We will be useful to God and to the world, and we will not be thrown out to be trampled by men.

As Christians, we must always remember that we alone are the salt of the earth and the light of the world. As we represent Jesus Christ to the world, we are the hope of the world. May God help us even this day to be different from the world, that the world may benefit by our difference and come to glorify God the Father of our Lord Jesus Christ. Amen.