Matthew 05:13-16 - Are You a Witness?

By Rev Charles Seet

Preached at / Published Life BPC 8am & 1045am Svc, 2012-02-12

Text: Matthew 5:13-16

This morning we continue with our present series of sermons on the parables of Jesus. One thing that all these parables reveal is the great skill of our Lord in teaching spiritual truths. Whenever Jesus taught spiritual lessons, He was able to captivate crowds of people for hours. Mary of Bethany spent much time sitting at His feet and listening to Him. When the Samaritan woman at the well heard Him teach, she went to town to tell others that they must come and hear Him. What was it that drew people to our Lord's teaching? Well there are three things. Firstly, it was marked by originality and authority. All that the Scribes could teach was what they had memorised in their schools from their received traditions. The people heard the same things from them over and over again until they were tired of listening to them. But when Jesus taught them, it was like receiving refreshing streams of water, full of cooling refreshment for their thirsty souls!

Secondly, the teaching of Jesus was marked by simplicity - Jesus taught the truths of God with the greatest clarity, and yet in the shortest communication. He did not have to use so many words to get His points across. The third thing that marked the teaching of Jesus was His creativity. He could use the most familiar objects that were found in every home to explain spiritual truths. We are now going to see one striking example of this. In Matthew 5:13-16 we see Jesus teaching us to be His witnesses by using things that everyone is very familiar with: Salt and Light. Through these He provides us with three good reasons why we ought to be His witnesses. The first reason is that

I. Being a Witness Ensures that We Are Not Useless

In verse 13 Jesus says that we are the salt of the earth. Salt has been a very useful commodity since ancient times. The Roman Historian Pliny said, 'Nothing is more useful than salt and sunshine.' In fact, salt is just as useful as the salary you are paid every month. How is this so? The word 'salary' comes from the Latin word 'salarium' which means salt given to a soldier as his wages. Yes, in the earliest times of the Roman Empire, soldiers were actually paid in salt. This gave rise to the expression, 'He is worth his salt.'

Salt was in demand in ancient times primarly because of its use in food preparation and cooking. And so, just as food is flat and tasteless without salt, so our Lord tells us that if we are not salty we are useless as Christians. He says this in v.13, 'Ye are the salt of the earth: but if the salt have lost his savour, wherewith shall it be salted? it is thenceforth good for nothing, but to be cast out' From this verse we learn two things that are true of a Christian who has lost his salty savour. Firstly,

A. A Christian who has lost his savour has no moral or spiritual influence on others.

This influence is represented by the word 'savour' which means 'taste' or 'flavour.' Salt is a useful seasoning which brings out the natural flavour of food. And that makes it important to those of us who love to eat. Do you know where the word 'salad' comes from? It comes from the Latin word 'salata' which means 'salted'? This is because the earliest form of salad dressing was to simply add salt to vegetables! 

Some of us like to add some sauce to our food, be it tomato sauce, chilli sauce or soy sauce. Actually the word 'sauce' comes from an old French word which means 'salted.' Another word derived from salt is salami, the large sausage used in pizzas - You can probably guess why it has such a name.

In the same way that salt provides good flavour to your food, we as Christians should provide a good influence upon the world around us. Our lives must be different from those around us. We must have the Christ-like characteristics which are mentioned just before our text (vv.3-9). To be poor in spirit, mourning for our sins, meek, hungering and thirsting after righteousness, merciful, pure in heart, and seeking to make peace: These characteristics are known collectively as the beatitudes (and they will be studied in detail in our next series of sermons). They can become ours only as we grow in our walk with the Lord. We need them because our savour as salt of the earth comes from them. It is only by living them out that we can be useful as a powerful influence on the people we come into close contact with. 

Our savour as salt of the earth will also help to bring the Gospel to people around us, and make them desire to turn to Jesus Christ for salvation. This is implied by another property of salt: It tends to make people feel thirsty. Our lives should create a thirst in the people we meet for Christ, who is the Water of life. Christ has said, 'If any man thirst, let him come unto me, and drink.' (John 7:37)

One good thing about salt is that it doesn't take much of it to bring out its full effects. A pinch of salt is all that you need. Similarly, all that is needed to make difference in a community is one Christ-filled life. In 1848, a Scots-Canadian missionary by the name of John Geddie came to an island in Melanesia which is known today at Vanuatu. It was inhabited by worst kind of savages who had killed and eaten 22 crew members of a British ship. These savages did not know what love is. Some even ate up their own children! But John Geddie bravely endured all kinds of trials and attacks from them. He learned to speak their language, and preached the gospel of Christ to them. He showed them what love and forgiveness is by his own life. He brought them to Christ and taught them to read and love God's Word which he translated into their language. After that, scores of them volunteered to bring the gospel to the neighbouring islands and many were killed by other savages. Years of labour and prayer brought an amazing transformation to the entire community. Today two-thirds of the population are Christians and half of that are Presbyterians. What did it take to bring about this transformation? One life!

After John Geddie died, a tablet was placed in the church he planted on Vanuatu with these words: 'In memory of John Geddie, Doctor of Divinity, born in Scotland, 1815, 'Missionary sent from Nova Scotia to Aneiteum for twenty-four years. When he landed in 1848, there were no Christians here, and when he left in 1872 there were no heathen.' Think of how God can use you to make such a difference if you retain your savour as the salt of the earth.

Besides being a useful seasoning, salt is also a useful preservative. In fact, until canning and refrigeration were invented, salting was the primary method of preserving food. It is still used to preserve food today. That is why we have kiam he (salted fish), kiam chye (salted vegetables) and kiam neng (salted eggs). Salt preserves food by killing off the bacteria which cause decay. For this reason it is also a very good antiseptic, and salt was used in ancient times to keep wounds from infection. Hence, we have the expression 'to rub salt into a wound.' It may be painful, but it is very effective!

In the same way that salt counteracts decay and prevents infection, we are useful Christians when we live in a way that counteracts the rottenness of sin in our world. Many horrible vices of ancient times have been eliminated from society primarily because of Christians who campaigned against them. E.g. In the 19th century William Wilberforce (1759-1833) successfully campaigned for the abolition of slavery in England. In the 1870s missionaries in China exerted a strong influence against the foot-binding of women and within 40 years, this thousand-year old practice came to an end. In India, the temple prostitution of little girls was finally banned through the influence of an Irish missionary named Amy Carmichael. What was it that enabled them to do these things? They were merely exerting their influence as the salt of the earth to counteract the awful rot and decay that sin had brought into the world.

Today, it is our turn to do the same thing. We must exert a similar influence to counteract some evils that have crept into society, e.g. legalized gambling, pornography and sexual perversion. Immorality and permissiveness are increasing at an alarming rate. Censorship rules have become less and less restrictive. The gay movement has grown a lot stronger and bolder within the last 10 years. What can we do about these trends? There are times when we need to make our views known in order to resist the strong tide of sin. We have to be like salt, exerting a seasoning effect upon the world for good, and being a preservative of society against evil. If we fail to do this, we may end up not only forfeiting our moral and spiritual influence on society, but we may also prove that we are counterfeit Christians. This brings us to what Jesus said in the latter part of verse 13.

B. A Christian who has lost his savour may not be a real Christian.

'It is thenceforth good for nothing, but to be cast out and to be trodden under foot of men.' Strictly speaking, there is no way that salt can lose its saltiness. Sodium choride will always have the properties of sodium chloride. Therefore when something that is supposed to be salt is not salty, it cannot be real salt. It is just white sand, which has no use other than to be trodden underfoot. This means that a Christian who has lost his savour may not be a real Christian, but is merely a pretender. Like white sand, he may resemble a real Christian, but he lacks the qualities of a real Christian. And if he cares about his own soul, he should examine himself to see if he is truly saved or not.

These words of Jesus in Matthew 5:13 are a strong warning to all of us. We should ask if we have lost our savour and become useless Christians. Have we become good for nothing and worthy only to be cast out and trodden under foot? If the Holy Spirit convicts you that this is true of you, please do something about it. Regain the savour that you have lost! Confess those sins that have drained away your spiritual vitality, and ask for the Holy Spirit's power to bear the characteristics mentioned in vv.3-9. Only then can you make a real difference in this world and be a good witness for our Lord Jesus Christ.

We now come to the other object which Jesus used to teach us why we must be good witnesses for Him: Light! I am sure we all agree that light is very useful because it helps us to see everything around us. Light was the very first thing that God created 'God said, Let there be light, and there was light' (Gen 1:3). Without any light we would all be in complete darkness, and it would be very difficult to move around. Have you ever walked in pitch darkness before? It is not a pleasant experience at all. 

I remember having to do that during night training when I did my national service 30 years ago. My platoon was out in the middle of a jungle on a moonless night and we were told to walk single file through a jungle trail in full battle order without using any torchlights or making any sound, so that enemy forces cannot detect us (This was before night vision goggles were invented). You can imagine how difficult it was to grope our way quietly through the darkness, all the while reaching forward to touch the back of the soldier in front just to make sure that he was still there. Without any light we could not tell where we were heading. We could not see any rocks, fallen branches or holes in front of us. That was a really scary experience. And what was even more scary was the fear of getting lost in the dark jungle and never being found! How good it would be to have light!

In the same way that we welcome light, those who live in a world of darkness would welcome lives that shine forth as lights. In the Bible, light always represents things that are good and desirable while darkness always represents things that are bad and undesirable. Light represents holiness, while darkness represents sin. Light represents goodness, while darkness represents evil. Light represents knowledge, while darkness represents ignorance. And light represents Truth, while darkness represents Falsehood. Because of sin, the world we live in is full of darkness and desperately needs all the things that light represents - holiness, goodness, knowledge and truth. And all these things are found in Jesus Christ. This brings us to the second reason why we must be witnesses for Christ'

II. Being a Witness Exhibits the Truth and Life of Jesus Christ in Us (vv. 14, 15)

Let us read what Jesus said in vv.14-15: 'Ye are the light of the world. A city that is set on an hill cannot be hid. Neither do men light a candle, and put it under a bushel, but on a candlestick; and it giveth light unto all that are in the house.' 

A. Do not Be a Secret Christian

Firstly, what Jesus said here teaches us that we cannot be secret Christians. We must not hide our light from the world. There are some people who are like that. They believe in Jesus Christ, but they do not want to confess Him before the world. Why? It is because they are afraid of the persecution that may come if people were to know that they are followers of Christ. They think that their faith in the Lord is a very personal matter between them and God alone, and so no one needs to know that they are Christians. They just want to remain 'secret Christians'. 

If you have been doing this, please understand that it is not a good thing to hide your Christian identity from others. If you do not want anybody to know that you are a Christian, you will soon have to compromise your faith. To keep yourself from being found out, you will have to live under false pretences all the time, and live in the same manner as all the unbelievers around you. You must walk like them, talk like them and dress like them. If you don't do these things, they may suspect that you are a Christian, and your cover would be blown!

A Christian is meant to be a witness of Jesus Christ. That's what you are. But how can you be a witness of Christ if you are ashamed even to bear His name? You are just like a lighted candle that is covered with a bushel, a container that is used for measuring grain. What use does that candle have? No one can see its light and benefit from it. It might as well just be extinguished!

In the same way, a Christian who cannot be a witness may as well not be a Christian at all. He will have to remain barren all his life, and he cannot win a single soul to Christ! I hope you can see from all this, that it is not good at all to be a secret Christian. Please do not be ashamed to let others know you are a Christian. Even though you may face ridicule, persecution and some inconvenience for doing this, you will be much happier, and at peace with God. You will find it really liberating and refreshing, because you won't have to live under false pretences anymore. But more importantly, you will be able to fulfill your role of shining brightly as a light of the world.

B. Be a Shining Christian

This is stated in the first part of v.16: 'Let your light so shine before men, that they may see your good works' The point that needs to be emphasised is that shining as lights is not an option, but a command we must obey. There are two other verses where the same command is spelled out: Ephesians 5:8 'For ye were sometimes darkness, but now are ye light in the Lord: walk as children of light.' Philippians 2:15 'That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world.' We must therefore do all that we possibly can to shine brightly as lights in the world.

But at the same time, we must be careful about how we do this. There are some pitfalls we must avoid in doing good works for everyone to see. These are revealed in what Jesus said in Matthew 6:1-4 'Take heed that ye do not your alms before men, to be seen of them: otherwise ye have no reward of your Father which is in heaven. Therefore when thou doest thine alms, do not sound a trumpet before thee, as the hypocrites do in the synagogues and in the streets, that they may have glory of men. Verily I say unto you, They have their reward. But when thou doest alms, let not thy left hand know what thy right hand doeth: That thine alms may be in secret: and thy Father which seeth in secret himself shall reward thee openly.'

How do we harmonise what Jesus said here with His command to 'Let your light so shine before men, that they may see your good works'? By looking at the difference in motives for doing those good works. The warning of Matthew 6:1-4 applies to good works that are done for self-glory, in order to earn the praises of men ('He is a very devoted Christian.') 

But the command of Matthew 5:14-16 applies to good works that are not done for self at all, but for the sake of others and most of all, to glorify God. Thus you must always be careful what your motives are, for doing good. 

You will notice that there are many lights here in this sanctuary. But do any of them shine in order to draw attention to themselves? No, that's not their purpose for shining. They shine so that you can see the things they illuminate like the words in your Bible and this pulpit area. The same principle applies to us when we shine as lights of the world. We are not to draw attention to ourselves, but to God. This is stated in the latter part of v.16 'and glorify your Father which is in heaven.'

This also means that we have to be selective in what we choose to do before men. Some things are best done in secret, away from public view, such as your daily quiet time and giving to God (not revealing the amount you give to anyone). But there are things which should not be done secretly, but also being careful not to do them to be praised by men - e.g. acts of love for people around you, showing concern for those in need, witnessing to your friends and loved ones. And when you do these things in the right manner and with the right motives, the Lord will be glorified. This brings us to the third and final reason why we must be witnesses for Christ:

III. Being a Witness Enables Us to Glorify Our Heavenly Father (v.16b)

This is stated in the latter part of v.16: 'that they may see your good works, and glorify your Father which is in heaven.' There are several instances recorded in the Bible where God was glorified through what someone saw in others: E.g. When a Roman centurion saw the way that Christ died on the cross, Luke 23:47 tells us that 'he glorified God, saying, Certainly this was a righteous man.' When the enemies of the Jews and all the heathen saw how Nehemiah and the Jews were able to rebuild the wall of Jerusalem in 52 days, they perceived that this work was wrought of God (Nehemiah 6:16). 

The same thing applies to you: When people can see that your acts of love are genuine and selfless, they will be moved to praise God for His love and grace. And when your friends who are still outside Christ are led to glorify God through what they see in you, they may also be saved from eternal death!

In some testimonies of salvation I have read, a new Christian testifies that what encouraged him most to come to Christ was not powerful preaching but something he saw in the life of his Christian friend that led him to seriously consider the claims of Christ. A song written by Ron Hamilton captures this quite well: 'When I enter heaven's glory And I see my Saviour's face, I will offer Him ten thousand years of praise. Then I'll find that special one in whose life I saw God's Son, And through tears of joy with trembling lips these words I'll say: 'I saw Jesus in you, I saw Jesus in you, I could hear His voice in the words you said, I saw Jesus in you. In your eyes I saw His care, I could see His love was there. You were faithful, and I saw Jesus in you.'

May this help us to understand that the light that shines in our life is meant to guide others to find salvation in Christ, who is the true Light of the World. Remember, that we are only small little lights compared to Jesus Christ who is the Great Light of the World. The brightest light of all is the light of Jesus, who said in John 8:12 'I am the light of the world: he that followeth me shall not walk in darkness but shall have the light of life.'

Please ask yourself whether your life is like that now. Can people see the light shining in your life - the light that will eventually lead them to Christ, the great Light of the world? Has anyone ever told you that what brought him or her to Christ was the light that shone in your life? If you have truly been saved and you love the Lord, then please do your very best to walk as children of light. In that way, you will become a good witness of the Lord Jesus Christ.

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