Salt and Light (Matthew 5:13-16)

Big Idea: Make a positive difference in a dark and decaying world by being distinct and reflecting Jesus’ light through your good deeds.

We are currently discussing evangelism in a series called "Too Good Not to Share." We’re looking at how to share the good news of Jesus with the people around us.

But we need to be honest. We’re scared. Someone I know taught week-long, masters-level intensive for the School of Mission, Ministry, and Leadership at Wheaton College, an evangelical liberal arts college and graduate school, and listed three things he learned, and this is one of them:

Evangelism is a perennial challenge.

Nearly everyone tells me that evangelism is tough, not only for themselves but also for the people they lead. It’s hard to train and motivate people to share their faith … And that’s true no matter where you come from. A discouraging word, yes, but it’s nice to know that virtually everyone struggles with that challenge.

Do you feel that? Evangelism is tough. Everybody struggles with this challenge. In fact, I was encouraged when I read a book called Honest Evangelism a few years back that began with these words:

I find evangelism hard. The problem with being an evangelist is that people assume that you find evangelism effortless; but I don’t find it easy, and never have. For me, telling people about Jesus has often been nerve wracking. But at the same time, it has been joyful.

One of the reasons it’s hard is because we don’t know how people will react. “If you are going to talk to people about Jesus, you are going to get hurt. It is going to sever some relationships. It is going to provoke people,” he says.

I think that’s the main reason why we don’t do evangelism. There’s no way around it: it’s hard. And we’re going to get to that in the coming weeks. Next week Nathan is going to be talking about how we can share our faith verbally.

But today I want to back up a step and talk about sharing the gospel with our lives. Don’t get me wrong: we have to share the gospel with our words too. That’s why Nathan’s sermon next week is going to be so important.

But how we live matters too. We need to both show and tell the gospel. This week is the first part: showing. Next week we’re going to look at the second part: telling. And then the week after that, we’re going to look at the fear issue and how to overcome it.

But let’s start here. In the passage we just read, Jesus instructs us gives us two images that tell us how we can begin to share the good news with others. The two images are salt and light. What does Jesus want us to learn from these images?

Three things, and then I want to spend a few minutes talking about how we can do this.

The world is dark and decaying.

Jesus says, “You are the salt of the earth.” Salt is a lot of things. For instance, it adds flavor and it purifies. But probably what Jesus means by this image is that salt preserves. If you ever lose electricity, a good way to preserve the meat in your fridge is to rub it with good dry rub salt. The salt draws out the moisture from the cells so that bacteria cannot thrive, resulting in dry meat that can last for months or even years without refrigeration.

When Jesus says that Christians are the salt, here’s what he means: “Christians have the effect of delaying moral and spiritual putrefaction,” writes D.A. Carson. “If their lives conform to the norms of verses 3–12, they cannot help but be an influence for good in society.”

The implication is that the world is decaying. When Jesus says that Christians are light, it also implies that the world is a dark place. Jesus spoke these words at a time of olive-oil lamps, not a time of streetlights and billboards, back when they’d didn’t need blackout blinds. It could get dark!

G. Campbell Morgan says, “He saw them wrapped in gloom, sitting in darkness, groping amidst fogs and mists, and He knew that they needed, above everything else, light.”

This should be my least controversial point today. Despite education and progress, the world is still dark and decaying.

You can pick up any kind of newspaper, and if you start going through it, you’re going to find—in the international section—terrorism and war and genocide. If you go through the national section, you’re going to find political payoffs and lies and scams and churches set on fire. If you go through the local section, you’re going to find rapes and abuse and murder and arson. If you go through the business section, you’re going to find scandals, fraud, and graft embezzlement. If you go through the sports section, you’re going to find drug use, illegal gambling, and adultery. If you go through the entertainment section, you’re going to find too many scandals and sins to even mention. No rational person can deny that evil—real evil—exists in this world. (Rick Warren)

If you want to ask why we need to show and tell the gospel, this is where we have to start. The world is not the way it should be. The world is in a state of decay and darkness.

Here’s the second thing we learn from these images:

Jesus calls Christians to make a positive difference in this world.

What does Jesus intend to do about the darkness and decay in the world? He tells us that we are salt and light.

Again, salt is a preservative. This means that we are to make a positive difference in this world. “What is good in society his followers keep wholesome. What is corrupt they oppose; they penetrate society for good and act as a kind of moral antiseptic. And they give a tang to life like salt to a dish of food.” (Leon Morris)

That means that Liberty Village should be a better place because Christians live here. We should not withdraw from society. We need to be, like salt, rubbed into the world. “This means that they must be Christians at work, Christians in politics, Christians at home, Christians everywhere else that a normal life in their own society would take them.” (James Montgomery Boice)

Side note: It’s crucial that we have enough contact with the world that we can be salt. I can’t wait until COVID is over, because we need to get back into the community. That’s what it means to be salt.

But we’re also meant to be light, a borrowed light. One pastor (Donald Grey Barnhouse) gives an illustration of what this means. He compares us to the moon:

When the sun goes down the moon comes up, and the moon is a picture of the church—of Christians. It shines, but it does not shine by its own light. It shines only because it reflects the light of the sun. Jesus said of himself in John 8:12, “I am the light of the world.” But when he was thinking of the fact that one day he would be taken out of the world he said, “You are the light of the world.” … You and I can show forth light only if we reflect the real light of the Lord Jesus.

“You will function a bit like Jesus himself when he was on earth, only in a smaller version,” he says.

What is God’s plan to deal with the darkness and decay of the world? Christians who live differently, who make a positive difference in the world and reflect Jesus’ light to others.

One more point, and then I want to talk about how to apply this.

We need to guard against failing at being salt and light.

Notice what Jesus says. In verse 13, Jesus says, “if salt has lost its taste, how shall its saltiness be restored? It is no longer good for anything except to be thrown out and trampled under people’s feet.” Salt can become so full of impurities that it becomes useless. When we stop living distinctly, we no longer have the preserving influence Jesus wants us to have.

But there’s another we can fail. “Nor do people light a lamp and put it under a basket, but on a stand, and it gives light to all in the house” (5:15). Our purpose is to give light. It’s to reflect Jesus’ light. Don’t hide it.

We can fail at showing the gospel if we lose our distinctiveness or if we go undercover. Let’s make neither of these mistakes.

Picture this: ordinary, sometimes scared followers of Jesus who are being transformed by his grace, and who make a positive difference in the world. In other words, we show the gospel.

You may ask how we do this. Jesus finishes in verse 16, “let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.”

Let’s close with this. First, make sure you have the light. If you haven’t come to Jesus and trusted him with your life, that’s the first step. He will make you new. Jesus came so that you could be made right with God. Turn to him and trust him today.

If you are a follower of Jesus, he intends for you to make a positive difference in the world by being salt and light. He wants you to live distinctively and to reflect Jesus’ light to others. We’re going to talk about telling the gospel, but before we get there, we have to start with showing the gospel by being salt and light.

How do we get started? I’m giving you a little graphic as a way to start. It provides five practical ways that we can be salt and light in our world starting right now:

• Begin with prayer. Pray for the people in your life. Ask for God to work in their lives.
• Listen. Before you speak, listen. Hear their stories. Ask good questions. Discover their needs, what they think, and sense where God is already at work.
• Eat. This is fun. I can’t wait to do this again. Share meals and spend time with others.
• Serve. Respond to the needs of others and help them in practical ways.
• Story. Share the story of Jesus and what he’s doing in your life.

I encourage you to download a copy of this bookmark and save it on your computer. Let’s commit to doing these simple things together.

These are all practical ways that we can show the love of Jesus in practical ways. We still need to tell — that will come next week — but it’s where we need to start.

Make a positive difference in a dark and decaying world by being distinct and reflecting Jesus’ light through your good deeds.

Lord, change us, and then use us. We pray this in Jesus’ name. Amen.