The Glory of Salt and Light

A sermon preached at Covenant Presbyterian Church of Fort Smith, Arkansas on July 8, 2018.

 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. You are the light of the world. A city set on a hill cannot be hidden. 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. 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 (Matthew 5:13–16 ESV).

Jesus’ ministry commenced with a simple message: “Repent, for the kingdom of heaven is at hand” (Matt. 4:17). Indeed, the kingdom of heaven was at hand and is as near as its King Jesus Christ. The message to repent and believe in Jesus is at the heart of the gospel. No one enters the kingdom of heaven apart from this.

But, while the kingdom of heaven came in the Person of Jesus Christ, the Son of God, it came first to reign in the hearts of those who repent and believe in Him. There would be no new theocracy in Israel, no new throne in Jerusalem, no overthrow of the Roman occupation through Jesus’ earthly ministry. Until His second coming, until the heavenly kingdom is finally consummated on earth as it is in heaven, citizens of the heavenly kingdom live in this earthly kingdom. The Christian is literally in the world but not of it. And we live in this world with divine purpose.

Jesus uses two metaphors to describe this divine purpose: salt and light. Jesus says, “You are the salt of the earth,” and “You are the light of the world.” Earth and the world signify the same thing: this temporal earthly kingdom, in contrast with the eternal heavenly kingdom. Is the Christian to isolate himself or herself in a sort of Christian commune? Or, is the Christian to immerse himself or herself in worldliness to be rendered unidentifiable? Jesus teaches neither of these extremes.

Note carefully these factual statements: You are salt. You are light. Jesus does not command: “Be the salt of the earth! Be the light of the world!” Rather, He is telling us what we are as citizens of the heavenly kingdom living currently in this earthly kingdom. What do these metaphors mean? What does it mean to be salt and light?

You Are Salt

While we take salt for granted today in an age of refrigerators and freezers, in the ancient world salt was the essential means of preservation. Salt can be used to preserve meat, fish, and vegetables. Due to the hypertonic nature of salt, most bacteria, fungi, and other organisms cannot survive in a highly salty environment.[1] Salt preserves, and in a sense purifies. The added benefit is that we need and enjoy the flavor of salt, a common grace blessing from God.

But, how is the Christian the salt of the earth? To answer this, consider the context of this passage: How does Jesus’ description of the Christian also describe the Christian’s spiritual preserving and flavoring effect in the world? According to verses 3-12, we are described as those who come into the kingdom of heaven spiritually bankrupt, poor in spirit. We mourn over our sin and are comforted in the gospel. As such, God matures us in meekness, as we develop a hunger and thirst for the righteousness of God. We extend mercy because of the mercy we have received. We live for God with pure hearts knowing that we grow in our relationship with Him as we live for Him. As far as it is up to us we live at peace with everyone, zealous to share the gospel of peace with anyone. As we live righteous lives for Christ, we are persecuted for it, for as the world hated Him so it will hate us. Nevertheless, like the apostles, we rejoice to be counted worthy to suffer dishonor for Christ.

Here in the Beatitudes we understand that we are recipients of God’s gracious favor through faith in Christ. We live for Christ because we are in Christ. The world around us however is like unpreserved food, progressively rotting. Apart from Christian influence, the world decays toward moral and spiritual putrefaction.

What does this salt-less putrefaction look like? The apostle Paul describes this moral and spiritual decay as being given up “in the lusts of their hearts to impurity, to the dishonoring of their bodies among themselves, because they exchanged the truth about God for a lie and worshiped and served the creature rather than the Creator…” (Rom. 1:24-25). In their idolatry, Paul says that God gave them up to “dishonorable passions. For their women exchanged natural relations for those that are contrary to nature; and the men likewise gave up natural relations with women and were consumed with passions for one another, men committing shameless acts with men and receiving in themselves the due penalty for their error” (Rom. 1:26-27). Paul describes such idolatry and wicked sexual deviance as an unwillingness to acknowledge God. So, God gave them up to “a debased mind to do what ought not to be done” (Rom. 1:28). As a result of this debased mind, “They were filled with all manner of unrighteousness, evil, covetousness, malice. They are full of envy, murder, strife, deceit, maliciousness. They are gossips, slanderers, haters of God, insolent, haughty, boastful, inventors of evil, disobedient to parents, foolish, faithless, ruthless. Though they knew God’s righteous decree that those who practice such things deserve to die, they not only do them but give approval to those who practice them” (Rom. 1:29-32). Such is the historical description, yet equally modern description, of a world without the salty influence of the Christian.

How then are we salt in a world that seems to be in a free fall of debauchery? Live as who you are in Christ! The problem is that we live as if there is no distinction between the way in which we live and the world around us.  We seem to be too caught up in what the world says are the significant issues of our day. The world doesn’t need your self-righteousness; it needs a Savior. The world doesn’t need your perceived moral superiority; it needs to see you mourn for your sin and be comforted in the gospel. The world doesn’t need your arrogant pride; it needs to witness a meekness that passes all understanding. The world doesn’t need your worldly relevance; it needs to see you supremely enjoying righteous living. The world doesn’t need your uninvolved condemnation; it needs your gospel-centered mercy. The world doesn’t need to see how sinful you can be; it needs to see the rare witness of a pure heart. The world doesn’t need your politics; it needs the gospel of peace that you are commissioned to carry to the nations. The world needs to witness the indescribable joy that comes from living in and for Christ.

Sadly, we lose our preserving and flavoring influence, our saltiness, when we do not live like who we are in Christ. When this happens, we who are the salt of the earth lose our influence. We become salt for the trail of moral and spiritual decay. You are the salt of the earth. Live like who you are.

You Are Light

In describing our citizenship in the heavenly kingdom, Paul explained to the Colossians, “[God] has delivered us from the domain of darkness and transferred us to the kingdom of his beloved Son” (Col. 1:13). Similarly, Paul reminded the Ephesians, “at one time you were darkness, but now you are light in the Lord” (Eph. 5:8). By God’s grace through faith in Christ we are in fact light shining in a dark world, shining as the light in the Lord.

Jesus describes this radiating effect to be like a “city set on a hill.” A city set upon a hill cannot be hidden by virtue of its position. Secured above, it radiates its light to the dark valley below. Likewise, positionally we have been raised out of the dark valley and placed on the hilltop to shine light in the darkness.

Jesus adds a second example: a well-placed lamp lights an entire room. What is the function of a lamp? It is to provide light. Why would anyone hide a light under a basket? It is absurd, irrational, to extinguish a lamp’s function by covering it. Likewise, why would anyone not radiate the light of the gospel? Like a well-placed lamp, like a city set upon a hill, God has made us as light to the world, because He himself is the light of the world (John 8:12).

As a light, God has providentially placed us upon the hills and stands of this world, in families and workplaces, in neighborhoods and on social media, in friendships both near and far. Sadly, many Christians have covered their light with a basket of worldliness. As the world watches, do they see a Christian witness at work, do they see a Christian witness in your family? Does your instagram shine the light of Christ? Are you known by fruits of godliness or worldliness? It is a sad testimony to be a light and never shine forth to a dark world.

Because we are light, Paul admonishes us, “Walk as children of light…Take no part in the unfruitful works of darkness, but instead expose them” (Eph. 5:8-11). That’s what light does. It shines light into the darkness. So, if you are salt, salt the earth! If you are light, light the world! This is our identity in Christ. Live like who you are.

And…know why you do it. Why salt the earth? Why light the world? What is our purpose as heavenly citizens in this earthly kingdom? Jesus said, “let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.”

Glorify God

The answer to the first question of the Westminster Shorter Catechism beautifully states, “Man’s chief end is to glorify God, and to enjoy him forever.” While this indeed is our chief end, it is unachievable apart from God’s sovereign grace. We who have been delivered from the domain of darkness and transferred to the kingdom of God’s beloved Son are the recipients of God’s love, mercy, and grace. In Christ we have redemption, the forgiveness of sins (Col. 1:13-14). We, therefore, were created and have been redeemed for the glory of God.

The glory of salt and light is God’s glory through us. You are the salt of the earth, so be salty to the glory of God. You are the light of the world, so be a light to the glory of God. In this sense, the Christian lives a life of worship, a defining characteristic of heavenly citizens. Consider the magnitude of this truth: Your life in Christ has a moral and spiritual preserving influence in this world; your life in Christ shares a testimony to a lost and dying world; your life in Christ, its influence and testimony, is a God-glorifying act of worship.

We were not redeemed to be sequestered to a monastic enclave. We were not redeemed to be undecipherable from the world around us. We were redeemed by God’s indelible grace to be salt and light. We are not salt and light for our glory but God’s glory, so “let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.”

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