What was the main message of the Sermon on the Mount, one of the most famous of Jesus' teachings? At the heart of Matthew's Gospel is the message of the kingdom. God has established His reign and rule on earth, not as an idea or concept, but in the actual domain of His dwelling and self-disclosure. Here on earth, He has established an outpost for His glory and for those who have peace with Him and been restored to Him in a new humanity. This is the message that John and Jesus brought to Israel. They declared that the main response to this message was to enter it through "repentance". To repent means to turn from the kingdom of the world and enter into the kingdom of heaven.
With this message as its backdrop, we understand that the Sermon on the Mount spans different sections in its extended development of this message. It takes for its central theme, the life and culture of this heavenly kingdom. In our previous study, we read the Beatitudes, which were 9 statements that showed what life in the kingdom is like. In that study, these Beatitudes were categorised into the Need, Help and Hurt Beatitudes articulating how the citizens of this new kingdom see their spiritual need (being poor in spirit, mourning, being meek); how they live lives of service and help to others (hungering and thirsting for righteousness, being merciful, being pure in heart, being peacemakers); and what they have to endure awaiting the future consummation of the kingdom in its fullness (suffering persecution for righteousness' sake).
Following the beautiful words of these Beatitudes, the next section of Matthew develops the idea of what life in the kingdom is like, what Jesus' disciples are to be and what will guide and govern their living.
(A) A kingdom shown in how we live (Matt 5:13-16)
Recall that the Sermon on the Mount is not a public address for the whole world, but specifically for Jesus' disciples. Thus Matthew 5:13-16 shows Jesus employing two metaphors to describe His disciples — salt and light. First, notice the plain statement Jesus makes that they are the salt of the earth (Matt 5:13). He explains how we are to understand this metaphor.
Jesus implies the value and usefulness of salt. In Matthew 5:13, we see that Jesus makes the point that salt is useful because it is salty and adds taste and flavor to food. If salt no longer does that, it has lost its value. In addition to being food flavoring, we also know that salt was useful as a externally added substance to be a preservative removing water content from food, and in doing so, reduces microbial activity and preventing decomposition.
By comparing His disciples to salt, Jesus was saying that they had a purpose in the world by being different and distinct as heavenly representatives in an earthly world. In Mark 9:50, we also see that Jesus speaks about a kind of peace that also exists in Christian relationships with God and with one another that must be guarded. Jesus insists that being His disciples and heavenly representatives makes them the salt of the earth because they add both flavour and prevent decay around them. Perhaps Jesus had in mind the idea that Christians were to live in transformed relationships with those around them marked by bloodbought peace. This is where our spiritual distinctiveness is seen: in how we treat other human beings made in the image of God. Our relationships show whether we are being distinct, and whether we belong to the heavenly kingdom.
In Ephesians 2:13-16, Paul tells us how that peace amongst one another is won. The Cross makes us salty. The death of Jesus breaks down dividing walls of hostility as we are saved by grace. We are stripped of any ability to be proud in ourselves. In Jesus' flesh, the law of ordinances and commandments are removed in that we are no longer measured by whether we qualify or fail since salvation is by grace. In this context, Paul refers to the Jews who had the Old Testament laws, and the Gentiles who did not. Paul’s point is that if salvation is by grace and nothing we merit is to our account before God, our spiritual pedigree, ethnicity or backgrounds have no powre to divide. The wall of hostility between the have and have-nots has been removed. Is there someone in your church or life that you are unable to forgive? Are you bearing a grudge? That is a dividing wall of hostility.
Thus, see how practical the gospel is. If we resurrect old wounds and act as if we are the judge over others, we are basically saying that Jesus’ work on our behalf is insufficient. Christians have peace with God and with one another through our Lord Jesus and thus we become the salt of the earth if we trust in Him. This is what Jesus implied at the start of His ministry, that those who repent and have entered His kingdom have become the salt of the earth, radically distinct from the world.
Next, Jesus also uses the metaphor of light. He does this two ways: Jesus speaks of a city set on a hill (Matt 5:14) like a limestone city elevated on a high place, gleaming in the sun so that all can see it, and also light in the house (Matt 5:15), which would have been the main way that pre-electrical houses were oriented, so that they could see by its illumination. The latter is an absurdist argument — no one would put on the light and then cover it. We are meant to see the similarity between the light and salt analogies with the use of “in the same way” in Matthew 5:16. As salt has its purpose, so does light. We should not abandon the purposes of being salty and offerin light.
Moreover, notice that the light is for others to see. What are they supposed to understand as others see the light? Jesus says others will see our good works and glorify our Father in heaven. It would appear that Jesus has more than the idea of performing good, moral, civic acts in mind if those actions reflect something of our heavenly Father. Rather, Jesus is talking about a kind of living that points people to the spiritual character of our actions and the divine source of our Father, the One who gives us our identity and the One whose image we are truly reflecting. Our good works show God's face in the world.
The aposlte Peter says something similar in 1 Peter 2:12 — “Keep your conduct among the Gentiles honourable, so that when they speak against you as evildoers, they may see your good deeds and glorify God on the day of visitation.”
In John 15:8, Jesus says this slightly different. He says, “By this my Father is glorified, that you bear much fruit and so prove to be my disciples.” Disciples are marked by fruit in their lives.
One should start to get uncomfortable in this. Realise that Jesus is not interested in our moralism and good performance. He is not interested in having nice disciples but is actually interested in spiritual perfection as salt and light. He is talking about a life that so marvellously expresses who God is that when non-believers look at our lives, they cannot help but exclaim that we are His because we live so differently.
These two metaphors present an incredibly high bar. Jesus is unrelenting in the way He describes what His disciples are. He states it as it is, not as it should be. Jesus' disciples are salt and light. How can this be? If we are honest, we should readily admit that we are not the salt and light of the earth. This is unattainable for us. We don’t live in a way that points to the Father and glorifies Him.
What’s the solution? Read on.
(B) A kingdom committed to the Bible (Matt 5:17-18)
Jesus moves on from life in the kingdom to what guides and governs the life of the kingdom. He marks out an inclusio between Matthew 5:17 and Matthew 7:12. The inclusion marks out the beginning and ending of a section of thought. This is bounded by the mention of the Law (first five books of the OT) and the Prophets (the Major and Minor Prophets) and everything in between - most likely a shorthand for the Old Testament in totality.
This section deals wiht God’s Word shown in the Old Testament, or the Law. Jesus stresses His correction - “do not think” - which is the reverse of His famous “truly, truly” statement. Jesus wants to make it clear that no one should think that Jesus has not to abolish and negate the Old Testament Law, but to fulfil it. Jesus has not come to make the Old Testament redundant.
How should Jesus' disciples understand Matthew 5:17-18? What does Jesus want them to understand about how He views the Old Testament Law? Simply: the Law God gave in the Old Testament is not meant to be neglected! Christ fulfils the Old Testament Law completely. Why does He want this to be known? What’s the utility of this truth, that Jesus fulfils the Law? The more Christians understand how Jesus fulfils the Law for us, the more we understand His righteousness on our behalf. This way, we are better able to understand and address our lived experiences of struggling with guilt feelings.
Chrisitans should read the Old Testament and understand the righteousness of our Saviour for us. Reading and understanding it should teach us that He is salt and light. Jesus fulfilled what the Psalmist wrote in Psalm 40:7-8 — “Then I said, “Behold, I have come; in the scroll of the book it is written of me: I delight to do your will, O my God; your law is within my heart.” Jesus was committed to live, as He told John the Baptist in His baptism, "to fulfil all righteousness" according to the requirements of the Law. And not one jot or iota will be missed out.
We may not have been faithful to God's righteous standards, but Jesus has been faithful for us. We don’t have the capacity to forgive or pray for our enemies, but Jesus does. We don’t have the heart to love and honour our parents as we should, but Jesus was the perfect Son. His righteousness is not to scorn us, but on our behalf.
(C) A kingdom of righteousness (Matt 5:19-20)
Jesus goes on to teach that those who live in the kingdom of heaven will never be slack about the Law (Matt 5:19-20). This helps us to understand the relationship between teaching and living out God's righteous standards and the kingdom of heaven. The Sermon on the Mount sets the bar so high, no human being can attain it. This should dispel any notion that Jesus was just a "moral teacher". In the next few weeks, we will see how Jesus takes parts of the Law and shows us just how unattainable His righteous standards are. In teaching us about life in the kingdom, we learn that nothing less than complete perfection and righteousness is required.
And yet, there are two ways to be righteous that the Bible speaks of. One way is to achieve it by our own efforts. This is a Law-righteousness which Jesus has been speaking of.
But there is a second way. Paul writes about in Romans 3:21, when he says “but now” signifying that something massive has happened that is different in the past. In the past, the righteousness of God was manifested in the Law, but now, the righteousness of God has manifested apart from the Law. This is a world-defining statement. History has been divided into two timeframes: a time when righteousness was seen only through the Law, and now, when a non-Law righteousness has appeared.
We understand that this is Gospel, or good news. God has opened up a new way to be righteous that does not involve obedience to the Law. Yet where can we read about this non-Law righteousness, Paul? Answer: in the Law and the Prophets - or the Old Testament itself that bears witness to this non-Law rightoeusness. Moreover we are told in Romans 3:22, this new way is through faith in Jesus Christ, for all who believe. This is faith-righteousness, a new pathway God has opened up to step out of our own record, and into the record of Another. To all who have faith in Jesus Christ, we are not just improved versions of ourselves! We who will never be righteous by our own record and merit, who can never be salt and light, are able to stand as if we were. Another's record is transferred to ours. We have found Someone else who did it on our behalf, and whom God accepts as our rightoues Substitute. Through faith in Jesus Christ, our sin goes to His Cross, and His righteousness comes to me.
The joy of being a Christian is to be able to say that we are the salt of the earth and the light of the earth because we are in Christ. He has fulfilled every bit of the Law for us! There is no more “me” and I belong wholly to Christ. This is what happens to us when we repent of our sins -- we turn away from ourselves and and turn to Him, step into union with Him by faith, and we enter into His kingdom of righteousness.
We need to be perfect to enter the Kingdom. And we can only be perfect in Christ.
What does this look like? Receiving and taking the Lord Jesus Christ as your Savior in an act of repentance and faith. Turn away from sin and self. Ask Him to be your Savior and to have His righteousness credited to you as your sin is credited to Him on the Cross. There is nothing more to do than trust Him and rest in Him. Trust in Him for that new life in the kingdom, trust Him to be everything to you. If you have never come to Christ and said that He is your life and new life, come to Him and receive His righteousness.
If you are a Christian, why do you look to your own when we have such a perfect record in Christ? Why would we walk away from that and trust our own works? Bring also your lingering guilt and shame to Him! He knows what to do with it.
How is God’s word calling you to respond?
Read more about how we can be righteous and live righteously in this blog post.