Salt and Light

Before we read our text for today, we need to build on what was said last week. The sermon on the mount is a sermon about repentance and the kind of life that repentance brings with it.

Repentance leads us to a kind of life that Jesus blesses, but the world rejects. Jesus blesses the poor in spirit, the meek, and the merciful. The world appreciates the sentiment, but it sees no real value in that kind of life. The world blesses the rich, the famous, and the powerful.

Repentance is turning from our impulse to find happiness in what the world values and instead turning to Jesus and life in His kingdom. Matthew 5:10-16:

10 “Blessed are those who are persecuted for righteousness’ sake, for theirs is the kingdom of heaven.

11 “Blessed are you when others revile you and persecute you and utter all kinds of evil against you falsely on my account. 12 Rejoice and be glad, for your reward is great in heaven, for so they persecuted the prophets who were before you.

13 “You are the salt of the earth, but 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.

14 “You are the light of the world. A city set on a hill cannot be hidden. 15 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. 16 In the same way, let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.

Verses 10-12 together form a single beatitude that is repeated twice by Jesus for emphasis and then further explained by two metaphors in verses 13-16. That’s why I’m separating it from last week.

But the previous beatitude, “blessed are the peacemakers”, is an important connecting point in the sermon, because peacemaking may bring persecution.

The efforts of Christians to live the kingdom life in a world that rejects the King will make us targets. No servant is greater than his master. They persecuted Jesus, they persecuted his disciples, they will persecute us.

Peacemaking is an attempt to reach people with the Gospel and walk beside them in repentance and faith. It is an attempt to build bridges between the kingdom of God and the kingdom of the world. But maybe you’ve heard the expression, “Bridge people get walked on.”

In 2 Corinthians 2, Paul says that “we are the aroma of Christ among those who are being saved and among those who are perishing.” To some we smell like life, but to others we smell like death.

Have you ever had an animal die in your attic or in your walls? It’s not a pleasant experience. You only know it’s there because of the smell, but the smell is bad enough that you will do anything to get rid of it. You can’t live with it, it’s so bad.

And that is how the Gospel is received by most of the world, according to the Bible. Some people are drawn towards Christ and His kingdom. But to most people, the Gospel is so offensive that they can’t tolerate it. They must get rid of it. And that’s why persecution exists.

Jesus specifically reminds his disciples of the prophets, who were often persecuted for the messages they preached publicly. Prophets were persecuted because they were saying things that disrupted people’s way of life. Their very presence was a criticism of the way people were choosing to live.

The prophets were exposing all the ways in which people were living outside the boundaries God had set for their lives. They were condemning people’s love of money, their neglect of the poor, and their broken sexual ethics. They were hated for it. And this is what Jesus wants for His disciples. We are being called to be a prophetic presence in the world, and Jesus uses two metaphors to explain how it works.

The first is salt, verse 13.

You are the salt of the earth, but 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.

This requires some explanation because the salt we buy today is much different from salt they used two thousand years ago. Our salt is pure sodium chloride because we have refineries, but their salt was not pure at all.

The white dust they called “salt” was actually only part sodium chloride and was easily affected by moisture. The salt could be washed out and the white powder that remained was nothing but dirt. It looked like salt, but it was worthless.

With that explanation, it is obvious what Jesus means here. This is the Christian who has become no different than the world. This is the Christian who has no prophetic presence in the world because they are essentially no different from the world.

But what exactly has been lost? Again, this requires a bit of explanation. If we want to preserve meat, we put it in a deep freezer. Back then, the only way to preserve meat was to cover it in salt. That was the primary purpose of salt – to slow the decay of meat.

In other words, Jesus wants his disciples to be different enough from the world that our prophetic presence in the world helps to slow the decay of sin and death. When God’s people live a life of daily faith and repentance, the fruit produced by that behavior—the character Jesus outlines in the beatitudes—will have a positive effect on the world around us.

Christianity is good for the world, even if the world rejects our beliefs. Incidentally, this is something that even scientists are beginning to recognize. While more and more people are now describing themselves as atheists or non-religious, science is demonstrating that, in general, religious participation is actually good for people’s health and happiness.

Jonathan Haidt is an atheist and a social psychologist. Listen to what he wrote:

“Surveys have long shown that religious believers in the United States are happier, healthier, longer-lived, and more generous to charity and to each other than are secular people… Religious believers give more money than secular folk to secular charities, and to their neighbors. They give more of their time, too, and of their blood.”

The influence of Christianity has led to many of the advancements we take for granted in society. We are salt, slowing the decay of sin and death in a world running from God.

But only if we are different. I like the way Dan Doriani makes this argument in his commentary:

“If the only visible difference between Christians and secular people is that we go to church on Sunday and give money away more regularly, why would anyone want to join us? If we divorce, alienate our children, tell lies, and make dirty deals like everyone else, why not play golf on Sunday and spend our money on exotic vacations?”

And the truth is, in many of our churches, Christians are not much different from the world. The salt is in grave danger of losing its saltiness and the world will suffer as a result. A church that is no different from the world is worthless.

But there is another consideration. Notice that Jesus chose salt as the illustration and not sugar. Listen to what one writer says about this:

“To look at some Christians, one would think that their ambition is to be the honeypot of the world. They sweeten and sugar the bitterness of life with an all too easy conception of a loving God… but Jesus, of course, did not say, ‘You are the honey of the world.’ He said, ‘You are the salt of the earth.’ Salt bites, and the unadulterated message of the judgment and grace of God has always been a biting thing.”

Martin Luther agrees, saying that preaching the Gospel is like rubbing salt into people’s wounds. He writes that “the real salt is the true exposition of Scripture, which denounces the whole world and lets nothing stand but the simple faith in Christ.”

In truth, Jesus is the honey. But He calls us to be the salt.

The second metaphor Jesus uses is light. Verse 14:

14 You are the light of the world. A city set on a hill cannot be hidden. 15 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. 16 In the same way, let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.

This is a much easier metaphor to understand because light works the same way today as it did then. We have no doubt what Jesus means here.

Christians who hide their light are Christians who are refusing to be in the world. Our God-given purpose is to remain in the world, letting our light shine before others. We must be visible. We must live our lives out in front of the world, not hidden in our homes and our churches.

We cannot move away from the world. We must move toward the world as Jesus moved toward us. It is tempting to retreat from the darkness, to isolate ourselves in fear. But that would be selfish, and even faithless. Jesus is commanding us to shine our light before a watching world.

Of course, the light we carry is reflective. We can’t stare at the sun without burning our eyes, but we can stare at the moon. The moon is not really a source of light. It only offers a reflection of the sun’s light.

This is why people might see our light and give glory to God, not us. Our good works are only a reflection of the character of God at work in us.

And what does light accomplish? It reveals. It exposes. It clarifies. And remember from last week, that is what repentance looks like. God reveals our sin. He exposes us. He gives us a more accurate self-perception. We turn from our sin and towards Christ.

We begin to hunger and thirst for righteousness. And then Jesus leads us immediately towards others. He makes us merciful. He strips away the selfish motives and makes us ambassadors of peace. He makes us salt and light.

Salt and light – this is how Jesus describes our purpose. Prophetic presence in the world, but not of the world.

We must be different. We must be visible. And we will be persecuted, or God will be praised. Those are the two possible responses, according to Jesus. If neither of those things is happening, then we probably are not really living our lives as disciples of Jesus. We may not be living out our purpose as salt and light.

Let me say that again – if we face no persecution for the way we live, or if God is not being praised by others for the way we live, then something is wrong. We are either too much like the world around us, or we are retreating and hiding from the world altogether.

I want to end with the words of Jesus in a prayer to His Father just before His death. Speaking of his church, Jesus said:

I have given them your word, and the world has hated them because they are not of the world, just as I am not of the world. I do not ask that you take them out of the world, but that you keep them from the evil one. They are not of the world, just as I am not of the world. Sanctify them in the truth; your word is truth. As you sent me into the world, so I have sent them into the world. And for their sake I consecrate myself, that they also may be sanctified in truth.

Church, this is why we are still here.