Verses 3-10 of Matthew chapter 5 describe the character traits that make up the essential nature of all Christians. Then, in verses 11 and 12, we find an elaboration on verse 10 explaining the proper response of a Christian to particular persecutions, which is to “Rejoice and be glad for your reward is great in heaven.” As discussed in the previous article in this series, “Jesus teaches that Christians who are persecuted for Christ’s sake alone should rejoice because the persecution is proof of who and what they are―a child of God and a disciple of Christ.”
Once Jesus has delineated the character of Christians, He wraps up His general description of the Christian character by speaking about the Christian’s walk among the human race. Matthew 5:13-16 states:
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.
Jesus used verses 3-12 to describe the essential character traits of a Christian―what the Christian is. These verses contain Jesus’ statement of the doctrine of the Christian character. In verses 13-16, He applies that doctrinal essence of character to the practical application in the believer’s life. He describes how the Christian character manifests in their interaction with the world. Let’s look at these verses to understand how Jesus summed up these foundational presuppositions of the Gospel of Christ.
EXPOSITION OF MATTHEW 5:13-16
“You are the salt of the earth.” Jesus first tells His disciples that they are the “salt” of the earth. He uses this salt metaphor probably because the people of His day would have been very familiar with salt. They would know that it was a preservative to prevent organic foods such as meats from putrefaction and from becoming rotten and unfit for consumption. The people would also know that salt was a flavoring agent that improved the taste of the foods to which it was added.
Christians are preservatives in the world in that their character and the gospel of Christ that they share with those in the world have a positive effect on unbelievers, some even unto belief in Christ. By faithfully presenting the true gospel, Christians work to prevent moral decay. There are situations when the presence of a known Christian prevents corrupt behavior from people, such as telling off-color jokes or speaking falsely about others, etc. The preservative effect of Christians comes not from mere church membership but from a known reputation as a person of God who possesses the Christian character described in verses 3-12.
As salt is a flavoring, so is it with Christians. Only a small amount of salt in relation to the whole is required to enhance its flavor. Likewise, though Christians are few compared to the whole world, Christians can improve the moral condition of the entire world through their godly character and the spreading of the good news of Christ.
“but if salt has lost its taste...” Jesus, having just said that Christians are the salt of the earth, immediately gives a warning. Christians must be pure salt; their character must not contain impurity, and their gospel communication must not contain impurity. Jesus is teaching that all Christians must be pure salt in that their character remains pure according to His teaching in the Beatitudes and elsewhere in Scripture and that they must stay true to the revealed Word of God as they spread the gospel to the world.
Salt, sodium chloride, doesn’t lose its flavor or taste. As long as it is chemically sodium chloride, it maintains its “saltiness.” When Jesus states that “salt has lost its taste,” He refers to the impurity of what was pure salt. In other words, substances other than pure salt have been added, altering salt’s ability to preserve and flavor as it did in a pure state. Jesus uses this phrase to refer to the Christian altering the required Christian character metaphorically revealed here in the Beatitudes or adding to or otherwise altering the pure gospel message. When this happens, damage is done to the presentation of the gospel because of the flawed character of the presenter and because of the communication of something less than the true gospel.
Salt is completely different from the medium into which it is introduced as a preservative or flavoring agent. This difference allows salt to exert its desired effects on the medium. This is the metaphor Christ uses regarding the Christian. All Christians are, in essence, different from the world, and it is precisely this difference that allows the Christian to do the good works of God in spreading the gospel. So, the Christian must guard against taking on characteristics and ideas that serve to adulterate what was pure.
Thus, the Christian character must duplicate, without adulteration, what Jesus describes in these Beatitudes, and the message they expound to the world must be true to the revealed Word of God.
“except to be thrown out and trampled under people’s feet.” Some salt deposits occur naturally, laced with various other types of minerals. Salt in this corrupt state cannot be used as a preservative or flavoring. This adulterated salt mixture is, therefore, spread on roads and paths, where it forms a hard base that kills plant growth. This metaphorically illustrates the deadly effects of an impure Christian character and an impure gospel message.
“You are the light of the world.” Jesus first deals with what the Christian is― “You are the salt of the earth.” Only after He has done this does He move on to what the Christian does.
Scripture tells us that the world is a place of darkness (Eph. 6:12, See also, 5:8), referring to the unbelieving human world. We are also told that Jesus is the light of the world and that His followers “will not walk in darkness, but will have the light of life” (John 8:12).
Not only does Jesus teach that the world is a place of corrupt darkness, but He also teaches that only Christians can give light-producing counsel and knowledge regarding its dark state.
Christians are the light of the world by exposing the corruption hidden by darkness. The Christian presence in the darkness will, by contrast, expose the behavior that has been hidden in darkness, and those who live in darkness will consequently see that corrupt behavior. Not only is the darkness exposed to light, but only the Christian can explain why it exists, and that reason is separation and alienation from God.
However, the light doesn’t end there. Christians expose the darkness and explain why it exists, but the Christian light shows those living in darkness the only way out of their eternal demise, namely, through Christ Jesus.
“A city set on a hill cannot be hidden.” The Christians and their faith and testimony regarding the gospel of Christ should be displayed openly in the world for all to see. A house on a hill is visible to all. Christians must not withdraw from the secular world but instead should be visible as Christians doing the good works of God.
“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.” Jesus is teaching that just as one lights a lamp to let it shine and give light to the entire house, so should Christians practice their faith, broadcast their testimony, and provide information about the gospel of Christ to everyone in their sphere of activity. Christians must not hide the light in Christ. They must make it available to all they contact or communicate with. “let your light shine before others.” All Christians are responsible for letting their light―their character and good works―shine so that the world may see and God may be glorified. Christians do this not for their credit and honor but so the world may honor God.