“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.” (Matt. 5:13)
Few things in creation are more ordinary than salt.
Most of us have interacted with it in the last couple of hours, whether we realize it or not. We use it to make leather, pottery, soap, detergents, rubber, clothes, paper, cleaning products, glass, plastics, and pharmaceuticals. It sits largely unnoticed on hundreds of millions of café and restaurant tables around the world.
Unlike pepper, which is often sitting next to it, salt is essential for our health and has always been eaten by human beings wherever we have settled. We add it to so much of our food that many languages simply distinguish between sweet and salty flavors. We spread it across roads when it snows. More than half of the chemical products we make involve salt at some stage. And that’s without mentioning the trillions of tons of it that sit in our oceans, covering 70 percent of the surface of our planet.
Salt is everywhere.
Its ordinariness and its use in all cultures make it an obvious candidate for Jesus to use as an illustration. Jesus, as we know, loved using everyday items to communicate truths about God and his people, and his description of the disciples as “the salt of the earth” (Matt. 5:13) is arguably the best-known example. To this day, people use the phrase to describe good, honest, humble people. Less predictably, it also features as the name of a Rolling Stones song, a D. H. Lawrence poem, and an intriguing variety of products including deodorants, water softeners, and (bafflingly) wine.
Here is the really odd thing, though: an awful lot of Jesus’s disciples, the very people whom he identified as the salt of the earth, are still not entirely clear on what he meant. Lots of us have heard explanations of it—our job is to make the world taste better or stop it from rotting—but these explanations often conflict with each other and suffer from various problems. Jesus was talking about salt in relation to the earth, not food. Salting the earth was something people did after destroying their enemies, rather than blessing them. Elsewhere in the Gospels, Jesus connects salt with fire and with living at peace together (Mark 9:49–50), neither of which seems to fit with the idea of tastiness or preservation. Technically, sodium chloride doesn’t lose its flavor anyway. So what on earth is Jesus talking about?
The reason it’s confusing is that salt had a number of purposes in the ancient world. At least five of them are relevant to Jesus’s words about his disciples: salt was used for flavoring, preserving, sacrificing, destroying, and fertilizing. Rather than assuming that Jesus’s statement is confusing and then debating which particular use of salt he had in mind, it’s best to assume he knew what he was doing and that metaphors can function in multiple ways. Followers of Jesus are like salt: although we’re ordinary and everywhere and get involved in pretty much everything whether we’re noticed or not, we also have a variety of roles to play as God’s kingdom comes on earth.
Let’s consider each of those five purposes.
Salt makes food taste better, either by adding flavor to something that would otherwise be bland (chips or fries), by enhancing flavors that are already there (vegetables), or by providing a contrast with a very different sort of taste (mmm, salted caramel). This is probably the use of salt that most of us think of, because it’s the only one of the five that still applies today. Regardless of whether Jesus’s original audience would also have thought of it first—and they may not have—it is a powerful illustration of the way Christians are to serve the world. We’re intended to spread throughout the world and enhance it, adding flavor to things that would be bland, drawing out the blessings of whatever is good, and providing a contrast by being distinct and different. When Paul tells us to ensure that our speech is “seasoned with salt, so that you may know how you ought to answer each person” (Col. 4:6), this is the kind of thing he has in mind.
Salt was the ancient equivalent of refrigeration. If you wanted to stop meat or fish from decaying, you could rub in salt and make it edible for longer. This was the main reason salt was so valuable. Roman soldiers were sometimes paid in salt, which (as an aside) is the origin of our word “salary.”
Disciples of Jesus, in this sense, are sent into the world to keep it from decay, preserving its goodness and preventing it from becoming corrupted or ruined, which is a helpful thing to bear in mind as we go to work every day.
Salt does not just savor. It saves.
This may well be related to the previous two functions of salt, although it is probably less familiar to us. Early in Israel’s history, Moses explained how Israel was to offer sacrifices to the Lord: “You shall season all your grain offerings with salt. You shall not let the salt of the covenant with your God be missing from your grain offering; with all your offerings you shall offer salt” (Lev. 2:13). Perhaps because it flavored food and kept meat from going bad, salt was a necessary part of all of the Isrealites’ sacrifices and even represented God’s covenant with them.
“Disciples are salt in this sense, too,” Peter Leithart writes. “The world is an altar. Humanity and the world are to become a single great offering to God. As we offer ourselves in obedient, suffering self-sacrifice, we become the seasoning on a cosmic sacrifice that makes it well-pleasing to God.”
This is one we find much less appealing, but we can’t get away from it: there are more scriptural references to salt being used in judgment or destruction than to any of the other purposes.
When Lot’s wife turns back to look at the city of Sodom, she is turned into a pillar of salt (Gen. 19:26), a story Jesus refers to when describing the day of his coming (Luke 17:32). Moses warns the Israelites that if they break God’s covenant, their land will be “burned out with brimstone and salt, nothing sown and nothing growing, where no plant can sprout” (Deut. 29:23). When Gideon’s son Abimelech tries to set himself up as king of Israel, the men of Shechem rebel against him, and he responds by razing the city and sowing it with salt (Judg. 9:45). The psalmist describes God turning “a fruitful land into a salty waste, because of the evil of its inhabitants” (Ps. 107:34). Jesus himself, in one of the fiercest judgment paragraphs in the Gospels, says simply that “everyone will be salted with fire” (Mark 9:49). Salt, in the ancient Near East, was used to express judgment upon evil.
There’s a sense in which disciples have the same purpose. God scatters salty Christians into the world as a way of judging evil, destroying wickedness, and preventing lust or greed or murder or injustice from taking root. The very existence of the church, preaching and living out the gospel, proclaims judgment against the enemies of God and serves as what Paul calls “a clear sign to them of their destruction” (Phil. 1:28); this may be why Jesus says we are the salt of the earth immediately after describing the persecution we will face if we follow him. Frequently, of course, the church has failed to live this way and has been an accelerator of worldly evil, not a brake. But Jesus knew that would happen.
That’s why almost all his words of judgment are directed to the people of God rather than the unbelieving world. We need to be salted too.
Several ancient civilizations used salt as a fertilizer for the soil, and depending on the conditions, it could help the earth retain water, make fields easier to plow, release minerals for plants, kill weeds, protect crops from disease, stimulate growth, and increase yields. The reason this matters is that Jesus specifically describes his people as the salt of the earth, which in a rural, farming culture would have been significant.
Disciples are fertilizers. We’re meant to be in those places where conditions are challenging and life is hard. We are sent to enrich the soil, kill weeds, protect against disease, and stimulate growth, and as we scatter, life springs up in unexpected places. Barren lands become fruitful. When the people of God are redeemed, as the prophet says, “the wilderness and the dry land shall be glad; the desert shall rejoice and blossom like the crocus” (Isa. 35:1).
So when Jesus said we are the salt of the earth, what did he mean? Did he mean that God will use us for flavoring, preserving, sacrificing, destroying, or fertilizing? In a word, yes. If people tell you that it’s about only one of those things, by all means hear them out. But take it with a pinch of salt.