Dear brothers and sisters in Christ, my family and those whom God loves:
I would like us to consider this text from the fifth chapter of Matthew’s Gospel, verses 13-16. Jesus said…
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. (ESV)
Jesus, after calling his first disciples (Matthew 4:16-22) begins to teach them (Matthew 5:2) the Good News: Blessed are you…Jesus repeats this blessing nine times (Matthew 5:3-11) and each blessing expresses both who these disciples are in Christ (poor in spirit, mourning…) and the present and future promises they have been given because of Christ (the kingdom of heaven, comforted…). This is their calling and identity and despite the persecution that Jesus says will come falsely on my account (5:11), these Gospel blessings lead the disciple of Christ’s to rejoice and be glad (5:12).
It is at this point that Jesus continues his summary of the calling of his disciples in terms of who they are (5:13-14) by declaring: “You are the salt of the earth…You are the light of the world.” One should not read too much into these metaphors since the salt and light they point to will be unpacked in the rest of Jesus’ sermon (Matthew 5-7). Unlike the previous beatitudes which were all Gospel, Jesus’ explanation here considers the possibility of disciples not being who they have been called to be (but if salt has lost its taste).
13 “You are the salt of the earth…
Salt in biblical times was a precious commodity. It was far more valuable than it is today. Although Jesus places emphasis on salt as a means of enhancing the flavour of food in this passage, salt also played an important role in preserving food and in cleansing. Again, we should avoid reading too much into either this metaphor or the next one. What is clear from the common message of both images for both John the Baptizer and Jesus is that the world is corrupt and people are being called to repent and believe the Good News of God’s reign in Christ (Matthew 3:2; 4:17).
Jesus statement You are… is addressed in the plural to all his disciples and no others. It is as declarative of who the disciples are as was Jesus’ earlier statements (Matthew 5:3-12): Blessed are you… Jesus saying, “This is who you are! This is your identity and your calling to salt the earth and later, to be light to the world.”
“You are the salt of the earth which prevents these disciples from forgetting their creaturely nature and where they have been called. Christ is not pulling them out of the world but seeding them into the world as messengers of his new creation.
Although Jesus has called these disciples to come through the door of blessing (Matthew 5:3-12) there may have still been a sense of uncertainty for them. “Can we be such blessed ones? Can we really salt or light up the world?” On the one hand, their identity is neither created or preserved by how well they do actually salt or glow. It is God’s Word that will go out and not come back empty (Isaiah 55:11). On the other hand, Jesus warns his disciples about not participating in who they have been called to be or even watering out the salt of God’s Word. This reference to being tasteless may also refer to the world’s dismissal of the salt that is trampled under people’s feet.
13 …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.
The possibility of salt losing its flavour is introduced by but if… Can salt actually lose its saltiness? A Wikipedia article (Matthew 5:13) notes the following:
Salt itself, sodium chloride (NaCl), is extremely stable and cannot lose its flavour. … Of the substances in this mix the NaCl was the most soluble in water and if exposed to moisture the NaCl would disappear leaving a white powder looking just like salt, but not having its flavour or its preservative abilities.
For salt to lose its flavour would require it removing part of its own chemical makeup. Is Jesus suggesting to these disciples that to lose Christ is to dismiss who they are: salt? How can one who turns away from Christ to unbelief be restored? Jesus offers no restorative possibility, but simply notes the consequence of salt no longer being salty: uselessness – It is no longer good for anything except to be thrown out and trampled under people’s feet.
Jesus is also pleading for involvement of his disciples in his mission. If you’re tasteless, how will the earth be salted (the mission)? Jesus considers his disciples to have a beneficial role in his mission and that role is one of salting the earth (like seeding). At the same time, it is not the disciples role to make the earth salty, but simply make sure the salt is spread.
From the image of salt Jesus now turns to the image of light, a far more common picture in the New Testament.
14 “You are the light of the world.
This is the same explicit declaration that Jesus made earlier to his disciples about being the salt of the earth. Again, Jesus is saying “This is who you are! You are the ones to bring light to the world – to be light bearers.”
Light has a revelatory function in two opposite ways. It can reveal all that is bad, evil, or not right and it can reveal what is good and true. In this way, the light can act as both Law and Gospel, revealing both our sin and our need for the Saviour.
That Jesus would describe his disciples as the light presumes that they have been blessed with the light of Christ already. This is not a light of their own making however, but one that is born in them and then begins to shine out.
Jesus also characterizes them as the light of the world. Like the phrase salt of the earth it connects these disciples to the world they have not been called from, but into. They are to be salt and light in the world that so desperately needs the salt and the light they bear.
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.
Unlike the image of salt which Jesus implies could lose its saltiness, Jesus uses two images that speak of the impossibility or ridiculousness of not shining once the light is in you. The first image is that of a city set on a hill. Modern readers don’t even need a city on a hill to understand the light that glows from cities at great distances. It is impossible to hide such cities.
The second example Jesus uses speaks to the purpose of light. One doesn’t turn on the light in order to cover it up with a basket or anything else. We light candles and turn on electric lights to help us and others see.
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.
Jesus draws his disciple back to their own purpose as light by calling them to let the light of Christ within them be revealed to those around them. The force of this command is similar to God saying in the beginning (Genesis 1:3), “Let there be light…”
Jesus’ statement so that they may see your good works… may cause some confusion for those of us who know we are not saved by works or may be uncomfortable with such a public display. How shall we correctly understand what Jesus is calling his disciples too here? First, Jesus is exhorting them to let the light of the Gospel be seen through their good works. The good works Jesus refers to will be explained in the remaining part of his sermon (Matthew 5:17-7:12). These works are to be public and visible and done with the sole purpose of bringing glory to the Father in heaven. Most importantly these good works are those that lead to the conversion of people, resulting in both faith and discipleship. Secondly, these good works ought to edify or build up the body of Christ (Ephesians 4:12). One can only glorify the Father if one first knows the Father rightly and this can only come through a right knowledge of his Son (Matthew 11:25-27).
These good works will be carried out through the ordinary vocations of Jesus’ disciples, but what will make these works extraordinary is how these works will be performed: in the purity, faithfulness, piety, love and generosity of the Holy Spirit’s power. It is the Spirit of Christ’s blessing in the lives of his disciples that distinguish his followers in their ordinary vocations from unbelievers who may be performing the very same jobs. Christ’s disciples are salt and light and this can be both seen and heard in the darkness of this world.
Shining the light of Christ through your good works does not guarantee that others will see Christ. They may see, but the primary purpose is to give glory to your Father who is in heaven and it is this purpose that must be kept in the forefront amidst whatever results may come, including persecution (5:12).
Dr. Jeffrey A. Gibbs in his Concordia Commentary: Matthew 1:1-11:1 (p.262) concludes with these words:
Both words and deeds are necessary. Words without deeds will not be heard. Deeds without words will bring no one to praise the Father in heaven. Each believing man or woman, layperson or pastor, stands as a disciple because of Jesus’ forgiveness and blessing, and receives Jesus’ calling to be salt and light. In the brightness of his light, our light will shine for the blessing and salvation of the world. For he teaches as one who claims authority and not as the scribes of his day (7:29).
What follows this section (Matthew 5:17-20) is Jesus’ dismissal of any thought that somehow he had come to get rid of or replace the Law or the Prophets. Instead, Jesus says, I have not come to abolish them but to fulfill them and calls his disciples to a righteousness that exceeds the scribes and the Pharisees.
Grace be with you,
– Concordia Commentary: Matthew 1:1-11:1 (pp.257-262), Jeffrey A. Gibbs, Concordia Publishing House: St. Louis, 2006.