Matthew 5:13-16 People of Salt and Light

Well, this morning we take yet another step into Jesus' teaching discourse on the Sermon on the Mount. The King is defining life in his kingdom for his disciples. Last week, in looking at the first 12 verses, known as the Beatitudes, we saw a series of nine statements that Jesus taught us as the kind of characteristics to be found in those who are truly blessed.

Jesus' words are completely polar opposite to that which we would find in the world and what the world might call blessed, such as blessed are the popular, blessed are the wealthy, blessed are the ambitious, blessed are those with great accomplishments. Jesus' Beatitudes are polar opposite to what we might find the world says is blessed, and Jesus showed us the upside-down nature of life as citizens in his kingdom realm.

So first we looked at those things which Christians are, just as a way of summary.

Christians are those who are poor in spirit, meaning they are deeply aware of their spiritual poverty and need of God's grace. Christians are also known by their gentleness or their meekness. Though wicked men believe the earth is inherited by force and oppression of others, Jesus says his people who will ultimately inherit the new creation are instead marked by a gentleness. Christians are also merciful, Jesus says. They are merciful. They are those who have been granted mercy in the gospel. They are ready at all times to render mercy to others. Fourthly, Christians are pure in heart. They are those washed from sin through Christ, and they have no interest in returning to the swamp of the world's pleasures and delights and fulfillments. Christians seek to live as in the presence of God and consecrate their hearts to him day by day.

We also looked at things which Christians do in Jesus' Beatitudes. Christians are those who mourn, meaning every true disciple is aware of their spiritual poverty and grieved at the sin that remains in them as in the world. Also, Christians are those who hunger and thirst after righteousness in their lives. They have come to know God, and they want more of God to grow in grace. Christians are also peacemakers. They do not desire quarrels or long-lasting disputes, but will seek to establish peace between parties as they are able.

And finally, we saw there are things which Christians experience because disciples of Jesus live these kinds of upside-down lives. Foreign to the way of the world, it means the church is distinctly different and at times it will be greatly hated by the world. Yet Jesus says it is, in fact, the blessed life to be persecuted for Jesus' sake.

So there's a bit of a summary of where we were last week. And now we turn to see the flow on from these words in the Beatitudes in verses 13 through 16.

Well, like I said, moving now into an introduction to these words. Like I said last week with the Beatitudes, first and foremost, Jesus is describing that which all true Christians already are. He's not telling us about something we need to become that we're already not. But he's really telling us something we have been made by virtue of our union in Christ.

And so really for Christians, then it's about maturing in the Beatitudes, maturing in the teaching of the Sermon on the Mount, because it's for those who are disciples. You cannot become a disciple of Jesus and become blessed by anything that is in you. It's one of the things that we will see as we move on. People often perceive wrongly that the Christian faith is simply moralism, a life lived by certain good principles. That's the Christian life. A lot of people believe that, but the Bible condemns such a teaching.

That which is needed to live the Christian life first comes from outside of you and from God. Jesus said in John 3:6, "that which is born of flesh is flesh, and that which is born of spirit is spirit. Do not be amazed that I said to you, you must be born again." So Jesus describes the born-again Christian's present state as being blessed. But here we see that Jesus is not yet finished in describing what Christians are by virtue of their union with him.

For in these next two verses, these next set of verses that we want to look at, we see another two attributes to add by way of metaphor. And these are that the Christian is both salt and light, salt and light. So really, my preaching point this morning for you is really quite simple. We want to see the kind of effect that Jesus' kingdom citizens will have on the world because of the radically different life that they now have in Christ.

What does that mean for the world? The world, you see, has a tremendous unrealized need for Christians to be Christians. The Christian church is something which alone God has purposed and equipped through the Holy Spirit to bring Christ's person to the world. No other institution has been given by God to bring his Christ to the world. That is uniquely the role of the Christian and the church.

And so as individuals, Christian families, as a local church, as part of the universal global body of Christ, we are salt and light for him in this world. One commentator I consulted rightly made the observation that Jesus' words very much anticipate the ending of the Gospel of Matthew and what we call the Great Commission. Jesus says, "Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, teaching them to observe all that I have commanded you. And lo, I am with you always, even to the end of the age."

I remember talking years ago to a friend who was a talented digger operator. His father actually owned a business that he ran some diggers as part of that business. And so naturally, he grew up driving a digger, extremely proficient even at a young age. And I remember talking to him, this would be 10 years ago, and he told me that at some point operating a digger becomes so natural to you that it feels like an extension of your own body. And so where his mind is thinking, there his hands will be moving the joysticks and so on.

And as I was thinking about that, you know, with respect to Jesus and his disciples, it's much the same. As one has said, Jesus' disciples are to be extensions of his ministry. Christ was salt and light to the world. Christians too are salt and light to the world. We become extensions of his own ministry. And the more that we walk with him and grow in the knowledge of Christ, the more we desire to be used by him. So we become extensions by nature of him in the world.

So the Christian life, you see, along with its message of Jesus Christ and him crucified, it's not a private life. It's not a personal life only. It's a public life. Salt and light are public metaphors that Jesus is using. It's to be lived before men, no matter who, no matter where. To the end that more might know of Christ's supreme worth and excellency. That more might learn of the everlasting salvation and life with God to be found in Jesus alone. That more might know of the great lengths and the love that God has so moved to redeem sinners and make them sons and daughters of God most high.

That more, as Jesus says in verse 16, that more might glorify your Father who is in heaven. That's the end goal of the Christian's public life as salt and light in the world. That more might glorify our Father who is in heaven. So the purpose of our witness for Jesus and the conduct of our lives is for worship. The author and theologian David VanDrunen asked this question. He said, "Where is the kingdom of heaven to be found? Jesus here points us to an earthly community that is the gateway to the kingdom." They are witnesses for God in the world. The church, the Christian, you see, is God's outpost testifying of him. And he leaves us in the world for him until he returns.

So continuing on, we simply want to consider two headings. First, Christians as the salt of the world. And secondly, Christians as the light of the world.

The Christian As Salt

So firstly, Christians as the salt of the world. Jesus was a master of the metaphor. He referred to sinners as lost sheep. He calls his kingdom like a mustard seed. He calls himself the bread of life. He compared his relationship to his people like vine and branches. So here we see another of Jesus' metaphors to describe the Christian and their relationship to the world. Jesus says, look again at verse 13, "You are the salt of the earth."

So the obvious question is, what does Jesus mean by this? We simply need to understand the function of salt, and we shall clearly see what Jesus is saying. Salt in the ancient world, interestingly, was a highly sought-after mineral. In fact, I even learned that there have been wars fought over access to salt. It can be sourced by evaporating seawater or mining rocks of salt deposits. It had two key uses, one of which is less common today. But the first use of salt is that it has a preserving effect.

Today, if we have meat, for example, we need to store. Well, we have fridges and freezers and modern technology, but it was not so in the pre-electricity era, of course. And by using salt, by rubbing salt all over meat, people could preserve food for longer than without due to its ability to inhibit the growth of bacteria and so on. So salt had a preserving quality to it. And now we see in the first place what Jesus is affirming, don't we? He's saying you, Christian, by virtue of your being placed in Christ are now salt to the world. There is a preserving quality that you will have in the world by virtue of your Christian faith, collectively as a church even.

Local and global, by God's grace, will have a certain restraining of sin and wickedness in the world. What might this look like, practically speaking? Well, at the individual level, you've probably all been in a situation, as I have many times, where a non-believer, having learned that you are a Christian, has said to you, "Oh, I better watch my language." And you might even find them apologizing at times for their language. They feel sensitive to the fact that you're a Christian. They understand that Christians don't use language like them, and they feel a wee bit ashamed, and they apologize. Sometimes they mean it very genuinely, and will restrain their foul language in your presence.

Well, even in a simple way like this, and you can develop some other illustrations in your own minds from that one, but even in a simple way like this, the Christian has become like salt to the world. A blasphemy which might have been spoken against the Lord has not exited the lips of the unbeliever because of the presence of a disciple of Jesus. See, the Christian is having a preserving effect on the world in this way. And if you scale this up, it's a tremendous impact on the world over. Do you see what Jesus is saying? R.C. Sproul put it this way. He said, "One task of the church is to help keep the world from self-destruction."

You see, the church must maintain its prophetic voice. And yet we need to understand the loudest voice that the church has in the world is simply that Christians live the Christian life faithfully in their homes, in their churches, in society. And it has a preserving effect on the society around you, the people around you, the people that you work with. It's a preserving effect.

A second aspect to the use of salt brings further meaning to Jesus' words. This use we're all familiar with. It's that we use salt for flavor, don't we? To season food for its taste.

It's nothing quite like some fish and chips on a Friday night with the table salt there to add to it. We all use salt in this way. Well, how does this use relate to the Christian life before the world? Well, we only need to ask what use is salt if it remains in the shaker and it's not used? Is it going to add any flavour? Is there any benefits of taste that are gained when the salt just remains on the table in the shaker and not used on the food? Well, there's none. There's no impact.

And you see, we have nothing to offer the world. No distinctives, no gospel of salvation to offer the world if we're only living private Christian invisible lives. No one even knows that we're a Christian. No one knows that we go to church on a Sunday. No one knows that we pray, that we read our Bible. It's all foreign from our public life. People ask us what we did on the weekend, and we just talk about the hobbies we pursued and not that we went to church to hear Bible teaching. No one knows. You see, it's like leaving salt in a shaker. What use is that? We're not adding any flavour. There's no seasoning to be added to the world.

But Jesus has a further point here about salt. Look at what we read next in verse 13 again. He says, "But if the salt has become tasteless, how can it be made salty again? It's no longer good for anything except to be thrown out and trampled underfoot by men." I read that in Jesus' time in Israel anyway, their primary source of salt was from the Dead Sea. And the salt harvested from the Dead Sea, it was renowned for its unique mineral composition, supposedly which was often mixed with a variety of other minerals, so it was often not pure salt.

But what could happen is this mixture could become contaminated and ruin the salt's inherent purity. And what the mineral that they could have, what would be a mixture of salt and some other minerals, and the salt could be washed out of it and it just becomes tasteless, like useless salt, not good for anything. This is what Jesus is talking about here. The salt has become saltless. And the application is clear. You see, our seasoning effect on the world, which is first and foremost in the proclamation of the Gospel to the ends of the world, it's made saltless and good for nothing when we become contaminated by the world.

We've got no distinctive quality. Might as well season your steak with sand. We've got nothing to offer the world if we don't have that preserving distinctive flavour, like salt. We've seen this increasingly in our day, for example. There's a number of churches now that will wave pride flags outside their doors, and they say, "We're welcoming to all, we don't judge," and so on, LGBTQI+ affirming churches. Well, essentially what they're doing is refusing to call sin, sin. They've lost their salt. The salt's in the shaker. There's nothing to offer. There's no preserving effect there. They just look like the world.

The church loses its saltiness when we lose our distinctiveness because we look like the world, we do things like the world does. So the world has nothing to receive from us in such a case. And so Jesus says we would be like salt trampled underfoot. You know, soldiers used to do that in wartime. They would take the salt of a village and they'd go spread it through the places where they'd grow their crops and trample it into the ground so that no produce could be grown. We've become useless and only for destruction if we do not have that preserving seasoning effect. So Jesus' point, I hope, is not lost on you here.

The Christian As Light

There is a second metaphor that Jesus uses, and this is our second heading: the Christian as the light of the world. Christian as the light of the world from verse 14. During the 19th century off the eastern coast of England, so the north-eastern coast, in the notoriously rough North Sea, there are apparently several hundred shipwrecks on the seabed floor. It was an immensely busy coastal route for ships in a previous era. I presume it's still used to a certain extent.

But over time, these wreckages were significantly reduced as a chain of lighthouses began popping up along the English coast. How many lives, I wonder, might have been spared in earlier times from dashing against the rocks by a flashing light of warning, giving position, indicating danger, guiding the way? That's the usefulness of a lighthouse. The Christian church, Christ's kingdom, is like a lighthouse to the world. That's what Jesus is saying to all his disciples, even you and I here this morning. Whether you realize it or not, every Christian is a lighthouse for Jesus. Some shine brighter, some are taller, are more noticeable, but all shine. So we want to take careful watch of the kind of light that we're emitting from our lighthouse.

Now, of course, Christ himself is the true light, isn't he? The Christian is to Christ what the moon is to the sun. We are simply reflecting the light of another. It's not our own light. It's the light of another. Jesus said, "I am the light of the world. He who follows me will not walk in darkness, but have the light of life." But what we are as Christians and what Jesus is affirming here on the Sermon on the Mount is that he has made us sons of light.

In John 12:36, Jesus said, "While you have the light, believe in the light so that you may become sons of the light." What's Jesus' point here then? This light is to be shone. It's to be emitted into the world. And so he explains this in verse 14. He says, "A city set on a hill cannot be hidden." It makes sense. Verse 15, "Nor does anyone light a lamp and put it under a basket, but on the lamp stand, and it gives light to all who are in the house."

In other words, just as a source of light that is under cover is nonsensical. And we might find other examples just as an alarm that makes no noise or that's also useless. It's like having glue that doesn't stick! Those things are nonsensical. They're useless. What God has done in Christians' hearts ought to reflect the light of Christ onto others, the world around us, from your neighbours to your work colleagues, to those you rub shoulders with at farming get-togethers. The Christian is to shine bright for Jesus.

And Jesus is here interested in not only our words, of course, but he's also specifically interested here in our good works. You'll notice in verse 16, he says, "Let your light shine before men in such a way that they may see your good works." Now, we know in the gospel that good works cannot contribute towards our salvation. Being a devoted churchgoer, a Bible reader, a prayer, these are all wonderful things, but they will not save you. Only Jesus' sacrifice on the cross, his perfect righteousness, only that will save you. So believe upon him for that gift.

But all whom Jesus does save, they have this new desire to perform good works for God. They want to live out what has been placed in them. That's what we see Jesus affirming. He's saying that even through a Christian, all through a Christian's manner of life, the way they conduct themselves, the way they order their business, the way they interact with people, all these things, God will use in such a way to bear witness of his work in your life. It's like a moth to the light to draw people to himself.

I was just reminded of a friend of mine that I met in the States last year. He was from New Zealand, but he travelled over with the same group as us. And his father was a bit of a hard man. He was in the SAS for many years and perhaps didn't have too good a relationship with his father. And one day his father went through a divorce. There was a marriage split up. And all of a sudden out of the blue, the father re-entered his life and was asking him for advice on how to deal with his marriage. And his son was married. He's got a young family now, I believe. He's living his life in such a way that it's bearing witness of the goodness and the work of God in his own life. And his father was drawn to that. And he came asking his own son for advice in his marriage. This is the kind of thing that Jesus is getting at here. We're often the only source of God's light to many people in all of our lives. And so Jesus says that the goal of these good works before men is that more might come, in verse 16, "glorify your Father who is in heaven".

Again, in the United States, one thing I remember noticing was the excessive size of everything. Their trucks are massive. Their hotels are massive. Their restaurants are massive. Their roads are massive. Everything is, even the people sometimes, massive as well. Everything's massive. And I remember going past this particular restaurant food chain. I can't remember which one it was. And the tower advertising this fast food chain. The tower itself advertising the restaurant seemed significantly taller than the water tower in Invercargill. It was just absolutely huge.

It just made me think, are our lives, our words, our good works, are they like a big oversized sign pointing to Jesus that no one can miss? No matter where you are in the city, you can look out and see this massive sign pointing the way to this restaurant. Is it like that in our lives? It's also worth noting that when Jesus says, "Let your light shine," this isn't supposed to be sending us out as like do-gooder Christians that people become weary of by their loud, proud, good works, which draw attention to themselves. Look how good I am. Look at how much money I'm giving to the poor, all these things. No, no, that's not what Jesus is talking about.

We don't want the big sign to be pointing at us. We want it promoting someone else. We're decreasing that Christ might increase. Jesus says this later on, actually, down in chapter six of Matthew, verse two. He says, "So when you give to the poor, do not sound a trumpet before you, as the hypocrites do in the synagogues and in the streets so that they may be honoured by men." No, we don't want to do that. So pay attention to Jesus' language here. He says in verse 16, "Let your light shine in such a way." There is such a way we can do it, and there's a wrong way we can do it.

In other words, so that the unbeliever might see Christ as that which upholds the believer's desire to do good to others. And when they ask you why you did that, you can then explain to them the gospel.

So let's conclude here. Supposedly during the early Reformation period 500 years ago, there was a man named Martin from Basel in Switzerland. And he embraced Jesus as his saviour, praise God. However, he was concerned about revealing his newfound faith to his acquaintances that he had, because he has rejected the falsehoods taught by the institutional church at the time. He was afraid, but he confessed Christ.

So he inscribed a statement of faith on a piece of parchment, and it read this, "Oh merciful Christ, I know that I can be saved only by the merit of thy blood. Holy Jesus, I love thee." And Martin then concealed this parchment behind a stone in his home, and it was in the wall. This parchment was not discovered or known about until a hundred years later. In contrast, another Martin, Martin Luther from Wittenberg, Germany, he also came to know the true gospel of Christ. And unlike Martin of Basel, Luther courageously proclaimed, "My Lord has confessed me before men. I will not shrink from confessing my Lord before princes and kings."

So there's the story of the two Martins, and I don't want to push the story too much. We don't know much about Martin of Basel in particular. But where do we find ourselves in that story? Which Martin are we? Is our light hidden under a basket, or is it known? Is it known by your unbelieving children, if you have any that are grown up? Is it seen by your grandchildren, this light? For behind a stone in the wall, it's insufficient. No one can see it. So pray that God would grant you help, that you would be salt and light in his kingdom for his glory.