Matthew 5:13-16 

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.

 

Sometime in the late 100’s AD, an unknown person wrote a letter describing the nature of the new religion, Christianity, and its adherents.  Today we call this the Letter to Diognetus.  It is fascinating since it is such an early description of the church.  The writer of the letter was impressed by the early Christians and what he called their “wonderful and striking way of life.”  Let me share a portion of that letter now.

[Christians] marry, as do all [others]; they beget children; but they do not commit infanticide. They have a common table, but not a common bed. . . . They obey the prescribed laws, and at the same time surpass the laws by their lives. They love all men, and are persecuted by all. They are unknown and condemned; they are put to death, and restored to life. . . . To sum it up: as the soul is in the body, so Christians are in the world. The soul is dispersed through all the members of the body, and Christians are scattered through all the cities of the world. . . . The invisible soul is guarded by the visible body, and Christians are known indeed to be in the world, but their godliness remains invisible.[1]

Of particular interest to us this morning is that summation sentence:  “To sum it up:  as the soul is in the body, so Christians are in the world.”

That is an utterly fascinating thing to say.  Indeed, I do not think a higher compliment could have been paid the early Christians.  What the writer of this letter seems to be saying is that the world itself is somehow different because Christians are in it.  In fact, the world is somehow better because the church is in it.  To use his imagery, Christians inhabit the world in the same way that the soul inhabits the body.  What that means is that the Christian church brings a kind of vitality and vibrancy to this world.

In truth, this anonymous person was saying something very similar to what Jesus said in the Sermon on the Mount, though he used different imagery in doing so.  Here is what Jesus said in our text:

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.

The unknown author of the letter to Diognetus likened the followers of Jesus in the world to the soul in the body.  Jesus used the imagery of salt and light.  The implications of Jesus’ metaphors are striking and revolutionary.

I. Followers of Jesus are, by definition, agents of preservation in a lost world.

Let us begin by first defining the significance of the metaphors.

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.

The two images were well known in that day just as they are in our own:  salt and light.  Salt has many functions:  preservation, purification, and flavoring, for instance.  While the Bible elsewhere mentions salt as a seasoning (Job 6:6, “Can that which is tasteless be eaten without salt,
or is there any taste in the juice of the mallow?”), it is likely that the primary function Jesus was thinking of here with his allusion to salt was preservation.  In a day before refrigeration, salt was the primary means of preserving meat.

That is also the case even in our day.  My dad is a hardware salesman.  He has spent his life in hardware stores, small and large, through the eastern half of South Carolina.  He told me once of going into a little hardware store in which he noticed an old burlap sack hanging from a rafter behind the cash register.  He asked the store owner what was in the bag.  “Country ham,” the store own replied.  My dad said that the ham must be very old indeed.  The store own replied that it was but that it was still perfectly edible as it had been salted so well.  Whether the store owner’s confidences were misplaced or not, he was certainly correct that salt is a powerful preservative.

If salt is primarily an agent of preservation, light is primarily a light of illumination.  Light illumines darkness revealing the truth that darkness conceals.  Light, too, is an agent of health and vitality.  We would not think of a life lived in darkness as an enviable life.

Let us also notice the definitive nature of Jesus’ language: “You are the salt of the earth…You are the light of the world.”  He does not say, “You will be salt,” or, “You can become salt,” or, “If you walk with me long enough I will make you into salt.”  No, He says, “You are the salt of the earth…You are the light of the world.”

Salt and light are therefore inherently connected to being born again.  If you are born again, you are salt and you are light.  To put it another way, being salt and being light is connected fundamentally to our justification in Christ, though, through sanctification, we grow into that fact more and more.

This is crucial.  This is key.  It means that coming to Christ means putting our feet immediately on the path of world transformation, preservation, and illumination as the presence of Christ in and through us touches the world.  Salt and light, then, are not the higher state of super Christians, they are the basic elements of the simple Christian.

It is not a question of, “Will I be salt?”  It is a question of, “What kind of salt am I being?”  Because, in point of fact, according to Jesus, you are salt and you are light.

It is also significant for us to realize something about the nature of salt.  “Sodium chloride,” D.A. Carson tells us, “does not lose its taste.”  This is true.  Salt, as salt, remains salt.  From a particular vantage point, the idea of salt itself becoming saltless is an impossibility.  But, as Carson continues, “the salt in use in first-century Palestine was very impure and it was quite possible for the sodium chloride to be leached out, so that what remained lacked ‘saltness,’ and specifically the salty taste.”[2]

Ah!  So salt, as salt, will always be salt, but salt infested by foreign unsalty elements can lose its saltiness.  This means that Jesus’ idea of salt losing its taste carries with it the idea of diluting pollution, for it is only through the introduction of polluting elements into pure salt that salt can lose its saltiness.  What this means for you and for me is that we were made to be salt and, when we walk with Jesus, we simply will be.  In order for us not to be salt we must allow unsalty elements to enter our lives and dilute the salt that Christ Jesus has made us to be.

Another important implication of Jesus pronouncement that “you are the salt…you are the light” can be found in the pronoun, “you.”  “You are the salt…You are the light.”  You, who?  You believers, you disciples, you who will trust me…you are salt and light.  This is critical not only because, in it, Jesus defines who is salt and light, but because, in it, Jesus defines who alone can be salt and light.

Only the people of God can be salt and light for the Kingdom of God, for only they are citizens of the Kingdom.  What this means is this:  at home, at school, at work, at church, if you are not salt, nobody will be.  If you are not light, nobody will be.  You are the salt!  You are the light!  It’s on you.  You!

Knowing this, we might ask, how can we be silent?  How can we be still?  How can we not speak?  How dare we not be salt and light?

Furthermore, the metaphors of salt and light say something about our basic disposition in and towards the world.  John Piper put it nicely when he said this:

The salt of the earth does not mock rotting meat. Where it can, it saves and seasons. And where it can’t, it weeps. And the light of the world does not withdraw, saying ‘good riddance’ to godless darkness. It labors to illuminate. But not dominate. . . . We don’t own culture, and we don’t rule it. We serve it with brokenhearted joy.[3]

Indeed, salt does not hate the meat it is trying to preserve.  Were it conscious, it might hate the decay and rot seeking to destroy the meat, but it would not hate the meat upon which the decay and rot were seeking to work their mischief.  Similarly, the primary disposition of the Christian in and towards the world ought not be and dare not be hatred and anger.  The Christian resides in the world as salt resides on meat:  with a recognition that the world needs the presence of the salt or else it will decay and rot and ultimately be thrown out.

How, then, do the images of salt and light tie into the idea of the Kingdom of God that we have seen rests at the very heart of our understanding of the Sermon on the Mount?  As it turns out, they rest naturally and easily in the Kingdom that Jesus preached.  Remember that we have said that the Sermon on the Mount is a depiction of what the Kingdom of God life looks like lived out in the kingdom of the world.  We have been using this image to depict the breaking in of the Kingdom of God into the world:

The Kingdom of God breaks into the world definitively in Jesus.  Jesus reigns in the hearts and minds of the crucified/resurrected community called the church.  This means that, today, the primary means by which the Kingdom of God is demonstrated before and enters into the world is through the born again lives of followers of Jesus.  And that means that the mores, values, ethics, truths, tenor, and tone of the Kingdom of God is lived out in the world in the lives of Jesus’ disciples.

With that crucial truth in mind, hear again the words of Jesus:

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.

If Christians are to be agents of preservation and illumination in the dying, decaying world, that means that the nature of this salt and light are the Kingdom of God values that have been imparted to us in and through the indwelling Christ.  Salt and light must therefore be Kingdom of God salt and light.  To be salt and light must therefore mean that we are bringing the preserving and illuminating realities of the Kingdom of God into the decaying kingdom of the world as we follow King Jesus in the world.

Being salt and being light does not mean forceful overthrow or violent coercion.  It does not mean a siege mentality or power posturing.  It simply means that we live out the values of the Kingdom of God within the Kingdom of the world.  New Testament scholar Craig Blomberg put it like this:

We are not called to control secular power structures; neither are we promised that we Christianize the legislation and values of the world.  But we must remain active preservative agents, indeed irritants, in calling the world to heed God’s standards.[4]

Blomberg’s reference to salt and light as “irritants” is telling and, it seems to me, very important.  It is important because it reminds us that this application of salt to the decaying, dying world structure is not a welcome application.  The world sees it instead as a gross imposition and uncouth intrusion.

It is a sad thing when meat has decayed for so long that it views the decay as normal and desirable.  It is a sad thing when the agent of preservation is resented by the very object it is seeking to preserve.  However, we should remember that the world’s hostility to the intrusion of the Kingdom of God life is itself a result of the decay that we are seeking to combat.

II. The temptation to abandon what we are is really a temptation to abandon Christ.

This inevitable opposition to the intrusion of the Kingdom of God into the kingdom of the world (which we discussed at length last week in looking at the eighth Beatitude on persecution) presents the church today with a very real temptation:  the abandonment of our function as salt.  This can happen in many ways:  rank abandonment, subtle concealment, or redefinition.

The Christian who embraces rank abandonment simply refuses to be salt and light.  In this case, Christ is usually imprisoned in something we call “the spiritual realm” (which usually means church services and functions) and we live like the kingdom of the world in something we call “the secular realm.”  The spiritual/secular idea is perniciously brilliant because it allows us enough Jesus to comfort our hearts but not enough to bring us in conflict with the world.  I am thinking here of the person who says that Christianity is their personal faith but they don’t carry Jesus with them into the workplace or the voting booth.  It is as if life has been reconstructed as a house with many rooms.  Jesus lives in the religious room, our favorite candidate lives in the political room, our favorite team lives in the sports room, etc.

A few years ago one of the major news magazines interviewed the novelist Reynolds Price on the subject of Jesus.  I will never forget that Price said he was personally very impressed with Jesus.  In fact, he said he tried to follow Jesus and live the kind of life Jesus prescribed. He embraced all of Jesus’ teachings, he said, except one:  the Great Commission, Jesus’ call for His followers to go into the world making disciples.  He wanted Jesus.  He just didn’t want a Jesus who actually called him to conflict with the world.

The Christian who embraces the tactic of subtle concealment is the Christian who keeps Jesus around, even in the world, but allows the kingdom of the world to whittle down the sharper edges and more scandalous elements of the teachings of Christ.  It is all very subtle and all very nuanced.  It is also very effective.

I suspect this happens frequently with “cool Christians,” by which I mean Christians who never quite seem ever to have to disagree with the world.  These Christians are very good with words.  Using words, they can deflect the uncomfortable aspects of Jesus while maintaining a form of godliness and a kind of Christianity.  They can even put up a front of prophetic courage on certain issues about which the world already has some basic agreement of outrage:  say sex trafficking, racism, or political posturing.  We must oppose these things and I applaud all who oppose them.  But it does indeed goad a bit when one meets Christians whose only challenges are to those structures that it has become acceptable to challenge.

And, of course, some Christians simply redefine Jesus, the gospel, and the Kingdom of God so that there is no conflict at all.  This is the “Christianity” of the niche Jesus:  gay Jesus, environmentalist Jesus, feminist Jesus, New Age Jesus, white supremacist Jesus, black power Jesus, liberation theology Jesus, cult Jesus, vegetarian Jesus, cage fighting Jesus, etc. and etc.  The redefinition of the Kingdom of God so as to make it fit into our desired shape is a popular and devastating tragedy.  It requires the outright gutting of the Kingdom of God as presented in the Scriptures and the insertion in its place of a kingdom that, strangely, looks just like us.  When we complete this terrible revisionism, we do not end up with the Kingdom of God but rather the kingdom of __________ (insert your own name here).

All of these are ways that we abandon our calling to be salt and light, to be the living, breathing presence of the Kingdom of God in the fallen kingdom of the world.  What is really important to understand is that the temptation to abandon what we really are is actually a temptation to abandon Christ Himself.

We are to be Kingdom of God salt.  We are to be Kingdom of God light.  Jesus is the King of the Kingdom.  It is His.  To abandon our high calling and privilege of being salt and light is therefore to abandon the commission of our King, Jesus.  To abandon the commission of our King, Jesus, is to abandon our King.

Brothers and sisters, if you refuse to embrace your identity as salt and light, you are refusing to embrace the One who makes you salt and light.  It is not just a matter of not living up to your calling.  It is a matter of committing treason against our King.

If you have come to Christ, you have come to the King.

The King has commissioned His followers to illuminate the dark world with His light.

The King has commissioned His followers to preserve the dying world with His salt.

It is only through the salt and light of the Kingdom that the world can come to know the King that it does not know.

It is only through your life that they will come to know of Him at all.

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.