*Ye* are the light of the world a city situated on the top of a mountain cannot be hid.
The Lord has just called His followers salt; now He tells them what they are to the wider world. The picture He uses is a hilltop city — no one can miss it. The commentators press two questions. Where does this light come from? And what happens when those who carry it try to stay out of sight?
A light for the world that had none
The two images point in different directions. One writer separates them, and notes that the disciples never chose to be this light:
The salt of the earth is a different thing from the light of the world. The earth, I think, means the sphere that already claimed to have received light from God. That light put it in relationship with Him, and gave it a definite shape before Him. The disciples of Christ were the preservative principle in the earth. They were the light of the world, and the world had no light of its own. This was their position, whether they liked it or not. It was God's purpose that they should be the light of the world. No one lights a candle to hide it.
Inward salt, outward light
The change of figure marks a change of direction. Salt keeps something from going bad; light travels:
But now, in verse 14, we have not only the principle of righteousness, but of grace — grace flowing out in strength. Here He gives the disciples a new title for their public testimony — "the light of the world." Light spreads. The salt is what ought to be inward, but the light is what scatters itself abroad. "A city set on a hill cannot be hidden." Its testimony was to spread all around.
Borrowed brightness
Jesus also called Himself the light of the world. So the same title on His disciples must mean something different. One writer explains the difference with the moon:
Our Lord says, "As long as I am in the world, I am the light of the world" (John 9:5). But in view of His absence His saints are called by Him the "light of the world" (Matt. 5:14; Phil. 2:15). Saints are light in the Lord (Eph. 5:8). They are here to show the moral characteristics of Christ to people who are in darkness. And the whole source and power of their light rests in the Lord of heaven. The world cannot see Him, but He shows Himself to His own by faith and in the Spirit. The moon shines at night because it stands in the light of the sun. In the same way, saints shine while Christ is away, because they stand in the light of the risen Son of God.
Why the city is visible
Anyone living in Israel would have seen the picture at once:
"A city set on a hill cannot be hidden." An enemy planning an attack could see it. So could a traveller looking for a place to stay. By day its white walls and buildings shone bright. By night the lights of the houses gave it away. So the walk of the Lord's disciples ought to be a light in this world, seen by everyone.
The invisible church
Some have argued that the true company of believers is invisible. One writer answers that:
But I read in Scripture, "You are the light of the world." What use is an invisible light? "A city set on a hill cannot be hidden." To call the true church invisible settles the question at once. It admits that the church has lost its original and essential standing. It admits that the church has left God's purpose and the order He gave it. God did not light a candle to put it under a basket. He lit it to set it on a lampstand and give light to everyone in the house. If it has become invisible, it no longer serves the purpose God formed it for.
Who the words are for
Commentators differ over whom the Lord is addressing here. Some hold that these words describe a faithful Jewish remnant who will bear witness after the church is taken away, saying that "as Matthew 5:13-14 shows, these godly Jews will be the salt of 'the earth' and the 'light of the world'" (H J Vine). Others press the passage directly on believers today:
Fellow believer, I urge you not to skim over or dodge the position the Lord gives you here on earth. These are His words: … "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." Let us live this out, instead of letting it slip past or pushing it off onto a Jewish remnant.
What can block the light
The lamp under the basket warns that something of our own can cover the light:
No one should put a lamp under a basket — that is, hide it behind what stands for man's own work. Let us not allow our work to get in the way of the light of Christ, who is the only source of light for people in darkness. The lamp set in its proper place will give light to all who are near it.
Summary
- Given, not earned — being the light is a position the Lord assigns, held "whether they liked it or not," not a status anyone works up to.
- Borrowed, not owned — the light is Christ's; His people shine as the moon shines, only because they stand in the light of the risen Son of God.
- Outward, not inward — unlike salt, which preserves quietly, light "scatters itself abroad" to a world that has none of its own.
- Visible, not hidden — enemy and traveller alike see a hilltop city. A light no one can see has stopped doing the job it was lit for.
- Clear, not covered — our own work in front of the lamp is what dims it. Keep the stand clear so people see Christ.