Introduction

This morning we are going to continue our study of the Sermon on the Mount by looking at Jesus’ familiar words in vv. 13–16 about being salt and light. But for the sake of context, I’d like to read vv. 11–16.

A couple weeks ago, we studied vv. 10–12, and I said that these verses feel increasingly relevant and heavy as our culture grows more hostile toward Christianity. For example, June has been declared Pride Month. We are going to be reminded a lot this month that the sexual revolution and the biblical sexual ethic are on a collision course and that the revolutionaries will not rest until they press everyone into their mold.

It’s scary to think about what faithfulness to God’s Word may cost us in the years ahead. Therefore, it’s very comforting to hear Jesus say that God’s blessing rests on those “Who are persecuted for righteousness’ sake” and to hear him promise, “Great is your reward in heaven.”

But the question remains, how do we endure the world’s hostility until the day we see Christ? Do we retreat from the hostility? Afterall, many people throughout church history have responded to the evils of culture and its hostility toward Christians by retreating into monasteries or convents.

Others have tried to cluster into exclusively Christian communities. And all of us are tempted at times to simply cut unbelievers out of our lives and to shield ourselves from the various challenges of living among them. It’s just easier and more comfortable to be with Christians who think like you and treat you with Christian love.

And Jesus anticipated this response to the world’s hostility; therefore, he immediately follows his blessing on the persecuted by answering the question, “Should we retreat from the lost or should we go after them?” He answers with two iconic illustrations. Christ’s disciples are “the salt of the earth” and “the light of the world.” First, Jesus tells his disciples in v. 13, “You are the salt of the earth.”

I.  Salt of the Earth (v. 13)

I’d like to point out 4 truths from v. 13. The first is…

Christians are different. This one is important, because so often preachers spend all their time on this passage speculating about how to become salty or how to become a light. Maybe you’ve heard a 10-point sermon from v. 13 based on 10 ancient uses of salt.

But those sermons all miss the fact that Jesus doesn’t command us to be salt and light. No, Jesus looks out at his disciples, and he says, “YOU ARE salt and YOU ARE light.” We are already different. The new birth has radically altered the core of who we are and our relationship to the world.

Our theme for 2021 is that we have been “Devoted to God.” We belong to God, we are different, and we have a different mission. God didn’t leave me here primarily to enjoy the pleasures of this world or to hide from it. He saved me to make me salt and light. It is essential that we embrace the privilege of our devotion to God and the purpose God has given us.

Now, I do want to go ahead and mention that v. 16 says the way saltiness and light manifest themselves is through “good works.” Throughout the NT, good works are primarily acts of care based on Christian love. It’s serving those who are in need and caring for the weak.

We love this way, because our Father is love, and his children will reflect that love themselves. So, Jesus is saying that one of the ways his disciples will function as salt and light is by their outstanding care for each other and for all people who are weak and needy. He’s going to say in vv. 43–48 that we must go to the very unusual length of loving our enemies.

And based on the emphasis throughout the Sermon on righteousness, we should also assume that righteous living is an important part of the good works that make us salt and light. We are different in our commitment to obedience, peacemaking, purity, marital faithfulness, truth-telling, etc.

It’s essential that we embrace this difference, because we don’t become salt and light by blending in with the world. The only way you will be salt and light is to stand out based on the love and righteousness that the new birth creates. This brings us to a 2^nd

Christians are influencers. Verse 13 compares us to salt. Again, lots of people like to speculate about the various ancient uses for salt and about what applications Jesus may have had in mind for all of them.

While those discussions may be interesting, they can distract us from Jesus’ basic point. Specifically, the reason salt has so many uses is simply because salt is impactful. It’s influential. Just a little salt really affects the taste of food. Salt preserves foods that would otherwise rot, and a little salt in an open sore really stings. Salt packs a punch.

And Jesus’ point is that someone who has been born again by the Spirit and is living a godly life will also be impactful. For example, listen to this story as told by former President Woodrow Wilson. “I was sitting in a barber chair when I became aware that a powerful personality had entered the room. A man had come quietly in upon the same errand as myself to have his hair cut and sat in the chair next to me. Every word the man uttered, though it was not in the least didactic, showed a personal interest in the man who was serving him. And before I got through with what was being done to me I was aware I had attended an evangelistic service, because Mr. D. L. Moody was in that chair. I purposely lingered in the room after he had left and noted the singular affect that his visit had brought upon the barber shop. They talked in undertones. They did not know his name, but they knew something had elevated their thoughts, and I felt that I left that place as I should have left a place of worship.”

That’s a perfect illustration of what Jesus has in mind. Yes, Moody had a powerful persona, but Wilson noted that he didn’t use his fame or his wit to make an impact. The other men didn’t realize who he was. Rather it was his genuine concern and godly testimony that impacted the room.

And if you are filled with the Spirit and manifesting the fruit of the Spirit, your life with have a similar impact. You don’t have to toot your own horn and put on some plastic show. No, genuine godliness stands out on its own and impacts others. The 3^rd truth, which doesn’t come up until v. 16 but needs to be stated now is…

Our goal is God’s glory. I want to go ahead and raise this issue, because we aren’t always clear about what impact Jesus is pushing. Some people claim that Jesus is only talking about gospel proclamation. To be salt and light is to be an evangelist. Others argue that Jesus is talking exclusively about social change, about making the world a better place though political activism, marching for social causes, and caring for the poor. Which is it?

We have to begin with what Jesus said. The goal is, “That they may…” So, the basic goal is that we would glorify the Father, by showing the world an accurate picture of his nature.

I want to be clear that this is a very different goal from the religious show Jesus will condemn in chapter 6. Jesus has strong words for those who give to the poor, pray, and fast in order to receive praise from men. Sadly, much of the social action of many churches and Christian organizations isn’t any better. It’s not that they really love people and want to help; rather, they want to put on a show to earn the world’s respect.

In contrast, the new birth inspires the impact of vv. 13–16. Believers “hunger and thirst for righteousness,” they are “merciful,” and they are “pure in heart.” Therefore, they genuinely love people, and they are genuinely passionate for God’s glory. We want people to see the beauty of our God through our good deeds.

And of course, we especially want them to know the glorious, good news of the gospel so that they can know our God for themselves and worship him as they ought. Therefore, we don’t just live the gospel; we preach the gospel.

I do want to emphasize that gospel proclamation is the fundamental way we are salt and light. No amount of food drives and political rallies can make an eternal difference without the gospel. So, evangelism has to be at the center of all our efforts to be salt and light.

But if we are zealous for God’s glory and we have been transformed by Christ, it will also affect other types of change. We will be merciful (v. 7) toward those who are suffering, whether it’s their fault or someone else’s. Therefore, we will be generous toward the poor, the addict, or the abused and we will do all that we can to help them.

And if we “hunger and thirst for righteousness” (v. 6), we are going to resist the rebellious spirit of our age. We will vote for politicians with integrity who oppose evils like abortion. We will challenge unbelievers about their sin and call them to repentance. We will be employers and employees, students, and community members who set a pattern of righteousness and truth and call them to follow our pattern. All of our words and actions we will be impactful.

And again, it will never be about me, my hobby horse, or my glory. No, I live an impactful life, because I am zealous for the glory of God. I want his name to be glorified in the earth, and I want sinners to know him in the gospel.

If we focus on God’s glory, we’ll naturally be shielded from the cooky and extreme applications that some people make of this text. Love God, be zealous for his glory, learn from his Word what glorifies him, and then go make an impact. The 4^th truth in v. 13 is a warning…

If we are tasteless, we are useless. Jesus warns, “If the salt loses…” Ancient peoples didn’t have the same advanced salt manufacturing that we have today. Instead, they had to find salt in natural sources. These sources were not always equally concentrated with salt, and they could become corrupted. Therefore, they were very familiar with “salt” that wasn’t actually salty.

And what good is unsalty salt? It’s like drinking decaffeinated, diet Coke or a sugar-free, latte with skim milk. It tastes terrible, it gives you nothing of value, and it destroys your kidneys. Jesus says unsalty salt is “good for nothing, but to be thrown out and trampled underfoot.” It’s worthless.

Now, I want to be clear that Jesus is not making a blanket statement about someone’s value or their salvation. Rather, he is specifically addressing a disciple’s impact for God’s glory.

In this regard, Jesus asks, what value is a disciple who blends in with a rebellious world and doesn’t stand out? I want to emphasize that salt doesn’t make an impact by being bland. So many Christians are consumed with fitting in with the world. They want to impact the world by being like it. That’s not how it works. Salt is impactful, because of its contrast. So, what impact will a disciple have, who doesn’t stand out from the world?

And what impact will a Christian have who doesn’t challenge the lost about their need of the gospel and urge them to believe on Christ? Jesus says that disciple is “good for nothing,” from the standpoint of spiritual impact. Wow!

So, ask yourself, “What impact am I making for God’s glory?” Do I stand out as a Christian in my family, at work, and at school? Do I give off an aroma of Christ that is distinct from the foul smell of the world? Don’t be a bland, tasteless Christian. Be someone who impacts others for God’s glory. The 2^nd illustration in vv. 14–16 is that we are the…

II.  Light of the World (vv. 14–16)

These verses largely reiterate and reinforce the message of v. 13, but they also add a couple of unique points. I’d like to point out 3 truths from them.

Christians must stand out. Verse 14 compares us to “a city that is set on a hill.” Most ancient cities were built up high, and at night their light stood out all around the countryside.

Today, with our powerful lighting systems, you can often see the glow of a large city from a long way away. Have you ever been out way out in the country on a dark night, and you can see a faint glow on the horizon? It’s incredible to think that city lights can be so powerful that they can impact you from 100 miles away.

In a similar vein, Jesus says that his disciples will shine like a city set on a hill. They will be a bright light against an otherwise the dark horizon.

The contrast is so important here, because it’s what makes the city lights impactful. Bright lights aren’t a big deal on a sunny day, but their contrast at night makes a huge difference.

That’s very important for us as we think about our place in the world. Again, so much of Christianity believes that we must be like the world to reach the world. If we want people to come to church, we need to make church feel and sound like the places unbelievers go. We need to use their foul language, dress in their immodest styles, and sing their music.

But Jesus strikes a very different cord. He says that contrast is what makes an impact. Now, we need to be sure that we are pursuing the right contrast. We don’t reach people by being weird for the sake of being weird or by being needlessly obnoxious.

No, the contrast comes from the marks of genuine godliness that Jesus articulates in the sermon—genuine, merciful love, true righteousness, sincere godliness, and gospel proclamation. These are the things that make us a bright city set on a hill.

So, embrace the calling of Christ on your life. Don’t sheepishly attempt to fit in with a godless generation. Instead, pursue Christ, love people, and preach the gospel. As you do, you will stand out as “the light of the world,” and Christ will use you to impact others. Jesus says that when you live this way, you “cannot be hidden.” A 2^nd truth about being lights is that…

Hiding the light is counterintuitive (v. 15). Jesus is probably thinking here of small oil lamps that were commonly used in the ancient world to light a home or to light someone’s steps.

We don’t really value light, because we have such easy access to it, and we are surrounded by light all the time. But a little bit of light would have been much more precious in Jesus’ day. Therefore, it would have been absurd to light a lamp and then put it under a basket. To do so would defy the very purpose of a light. It would be like taking a bath before you roll in the mud.

No, when you light a lamp, you put it on a lampstand, “and it gives light to all who are in the house.” That’s what a lamp is made for; therefore, that’s how we use it.

So, at this point, I want to return to the question with which I began today. How should we respond to the evils and hostility of our world? Should we retreat into our holy huddle? Should we hide from the most hostile regions of the world and stay where it is safe and comfortable?

What does Jesus say? He says that doing so, defies your very purpose as a Christian. When you got saved, God made you a light. You don’t put a light under a basket. No, the purpose of light is to shine!

Now, it’s also true that you don’t put a tiny lamp out in a torrential rainstorm. The water will overwhelm the light. So, we have to be wise about how we shine, and we have to be realistic about the threats that the world poses to ourselves and our families. If the world is impacting you more than you are impacting the world, you aren’t going to be an effective light.

Therefore, I want to be clear that Jesus is not telling you to compromise your faith by continually putting yourself in the way of temptations you are not strong enough to face.

But Jesus is also clear that the overall movement of the church should not be one of retreat from the world but of attack. We are going to see in our small group passage this week that Jesus prayed to the Father, “As You sent Me into the world, I also have sent them into the world” (John 17:18). God has not called us to be salt that is stashed away in the pantry or light that is hidden in a basket. No, we are to be salt and light in the midst of a decaying, dark world. This brings us to the 3^rd truth about the light, which is that we must…

Let your light shine. In v. 16, Jesus appeals to us, “Let your light…” Again, the point here is not that we go out and make a showy scene. Salt and light are impactful by just being what they are mixed in with food and darkness.

Rather, the point is that we need to go out and engage a lost and dying world. Build relationships with your neighbors and invite them into your home so that they get to see who you really are.

Get out in the community and rub shoulders with people, take an interest in them, and find out if they know the Lord. If you have a coworker or a family member who has real problems, don’t distance yourself from them for the sake of personal comfort; instead, love them and engage with them. Jesus challenges us to aggressively pursue the lost.

And then make sure that your light shines. Don’t let them be the ones who influence you; instead, let your light shine. Show them the mercy and righteousness of Christ. Share the gospel. Tell them that Jesus saves, and they need saving. Let’s attack a lost world with the only hope of salvation. Let your light shine.

Conclusion

Finally, I want to challenge anyone who is here that has never been born again. Understand that Jesus is not just giving a broad call to make the world a better place. No, this passage is deeply rooted in the transforming power of the gospel. You cannot be salt and light, unless Jesus lives inside you. You cannot “glorify your Father in heaven” and call others to do the same, unless he is your Father. So, let us talk with you today about your need of salvation and about what Jesus did on the cross to provide that salvation. Be born again today so that you can know the hope of the gospel and so that Christ will transform your life.