That Time Jesus Used Salty Language

In his most famous sermon, the most famous preacher in history said this: 

You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot.
You are the light of the world. A town built on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven.

These are some of Jesus’ most familiar words and most churchgoers have heard dozens of sermons about them. But there are some details you might not have yet considered.  

These are competing metaphors. Or, at least, they are disparate. They give us two models for the way we engage with unbelievers, and they are meant to be taken together. Jesus meant for us to have a couplet, and we should consider both lines of it. 

Consider, first, the properties of light.   

  • It dispels darkness.
  • It reveals hidden things.
  • It shows the way.
  • It works best when lifted up. A city on a hill and a lamp on a stand are both elevated.
  • It is separate from the things it illuminates. Light shines on things. 

It’s easy for church folk to draw parallels with our witness to the world. We imagine our churches as shimmering examples of piety that draw people to faith by sheer proclamation. But light-shining alone is only part of Jesus’ message here. Let’s consider salt. What observations can we make about salt that apply to Christian living? 

  • It fights decay. Our culture is rotting and we are meant to preserve it.
  • It creates thirst. We should live such winsome, question-begging lives that unbelievers crave more.
  • It works from the inside-out. Salt only preserves when it is pressed into meat.
  • It disappears in the dish it seasons. Salt doesn’t gain a lot of attention. Once applied to a dish, it is tasted but not seen. 
  • It is given up to the dish. Once you use salt on food, you can’t reuse that salt. It is spent. 

I think that Jesus creates a duality here to keep us from swinging too wildly to either pole of our witness. He says: 

  • You have to be completely pressed into the culture that you’re called to season, and yet you have to be set apart as a city on a hill.
  • You have to be invisible to the dish, and you have to let your light shine before men. 
  • You have to dispel darkness at the speed of light, and you have to prevent against rot that creeps in a snails pace. 
  • You have to be a lover of light and exposure, and you have to be an agent of intrigue that creates thirst for the invisible mysteries of God. 

Shining our light is the easier of the two metaphors Jesus used. Light is physical, mechanical, visible and instant. It’s flipping a switch. And it’s self-contained. It doesn’t have to mix with any other elements. It makes sense to our post-enlightenment brains. But salt has its effects invisibly, it requires chemistry, it takes time and faith. And it requires training; every generation in Jesus’ day had to train the next generation about the use of salt.  

It is easy for us to imagine lighting the way for our culture. We want our churches to pierce the darkness of a lost world and bring light to broken lives. But how eager are we to embrace the harder metaphor? Will we allow Jesus to press us into a rotting culture? Will we be content with invisibility? Are we willing to be given over to the neighbors we are called to season? Spent and used up in service to our world?  

Centuries before Jesus preached, another prophet connected this spending to light. He said, 

If you spend yourselves in behalf of the hungry
    and satisfy the needs of the oppressed, 
then your light will rise in the darkness, 
    and your night will become like the noonday. 

A church who shines her light is a good thing. Jesus says that leads people to see our goods deeds and glorify our Father in heaven. But a church who seasons her community — who creates a people thirsty for God and invites them to the Lord’s table to taste and see that he is good — is a more complete picture of Jesus’ commission. That is a body with a high, and savory, calling.