You are the light of the world. A city set on a hill cannot be hidden; nor does anyone light a lamp and put it under a basket, but on the lampstand, and it gives light to all who are in the house.

Let your light shine before men in such a way that they may see your good works, and glorify your Father who is in heaven. (Matthew 5:14-16)

Salt is hidden; you don’t see it at all. It just melts away into whatever it flavors or preserves. It works secretly to preserve from the inside. But light shines on the outside. Light is open, and light is working visibly.

In other words, the salt is the influence of Christian character. It is quiet, but it is powerful. Light is the communication of the content of the gospel. And so you have both sides. On the one hand, we live it; on the other hand, we preach it. On one hand, from the inside, we affect society’s thinking and society’s living by the power of our lives. On the other hand, we turn on the light, so that everyone can see the message we want to give.

And it isn’t just in our words. It’s in our very overt, open, godly conduct. We are not to be just a subtle influence like salt; we are to be a very open and blatant influence such as light. Salt can’t change corruption into incorruption. Salt only holds back the corruption. We have to turn on the light of the gospel to transform that corruption into incorruption.

If you study the Bible, you’ll find that light is related to the knowledge of God. For example:

For with You is the fountain of life;
In Your light we see light. (Psalm 36:9)

Your word is a lamp to my feet
And a light to my path. (Psalm 119:105)

Then Jesus again spoke to them, saying, “I am the Light of the world; he who follows Me will not walk in the darkness, but will have the Light of life.” (John 8:12)

So we see that God is light, the Word of God is light, and Christ is light; and that is the light that we are to shine on the world. We are to tell them about God, about God’s Word, and about God’s Christ. That’s letting the light shine. It’s got to be spoken, and then it’s got to be supported by a life that is consistent.

I think this is the primary duty of the church: to be light in the world and to spread the message of salvation. Having fellowship is wonderful, but sooner or later we’ve got to be light in the world and salt in the Earth.

Jesus says we have to be visible. We can’t just be a secret influence; we need to be visible, and the light has to shine openly. You are light, and light isn’t supposed to be hidden. You’re a city on a hill. The point is conspicuousness. We’re not just subtle salt; we’re very conspicuous light.

We’re not Masons in a secret society. We’re not pagans, with mysteries only for the initiated. We don’t have a cult known only to the few. We’re a city set on a hill. The whole world ought to see us.

You don’t take a lamp and put it under a basket; that’s absolutely absurd. But some of us have within ourselves the treasure of the gospel of Jesus Christ, and yet nobody knows about it. There are a lot of us who haven’t shared Jesus Christ with anyone in a long time. We’ve got a light all right, but there’s a basket over it.

Jesus says, “Let your light shine before men in such a way that they may see your good works.” If you have a light, you need to make it visible to others.

The light is there, right? If Christ lives in you, He’s the light. And you can’t change that. But you can put a basket on top of it so nobody will ever know. It may be the basket of fear, or of wanting to be acceptable, or of not wanting to offend. But whatever it is, you ought to get rid of it. You need to let the light shine by the way you live and the things you say.

Let it shine. Let the world see the beauty of your works. And in seeing your works, people will see the beauty of God Himself.

This post is based on a sermon Dr. MacArthur preached in 1979, titled “You Are the Light of the World.”