For a long time, I’ve been perplexed by Christ’s teaching on salt and light in Matthew 5:13-16.  (Please read it before going on.)

We’ve all heard people called “salt of the earth,” so that imagery doesn’t grab my attention, as it might have when Christ preached it to crowds on a hillside.  But when Christ talks about salt losing its flavor or saltiness, this once-serious chemistry student begins to snag: “What?  Huh?”  I’m not sure how salt—sodium chloride—could ever lose saltiness. Saltiness seems “built in” to salt.

Maybe Christ’s question is purely hypothetical: What use would salt be for food preservation or flavoring if it lost its saltiness?  However, I’ve also read that the “salt” people used in Jesus’ time might not have been especially pure.  If it got wet, the sodium chloride could leach out, and the remaining substance would not be very salty.   The needed zing would be missing.

In the next few lines, Christ talks about people not putting a lamp under a bowl or bushel because lights are lit in order to shine out. A common thread between salt (and its saltiness) and a lamp (giving off its light) is that both do their valued work by affecting what’s around them.

So, when Jesus calls us salt or lamps, it implies spreading his influence for the glory of God. People are sometimes said to be “hiding their light under a bushel” when they don’t radiate the lessons or blessings God has given.

In fact, Jesus has told us in many ways how this is supposed to work.  In John 15:5-8, for example, Jesus describes how our being connected to him, as branches to a vine, will result in “bearing fruit.”  His nourishment powers our fruit production, and, even when we haven't yet been fruitful, Jesus is willing to work to get us started (Luke 13:6-9).  Thank you, Lord!

Okay, we’re supposed to be salt and light, to let our good works shine out and influence people.  But now I’m snagging again—and not over chemistry, but Christianity!

I’ve also read the verses just a bit later (Matthew 6:1-4) that talk about not showing off good deeds.  For example, if we give to the poor, it’s supposed to be done so quietly that our “left hand doesn’t know what our right hand is doing.”  Similarly, Jesus tells us that if we fast or pray, it should be done unobtrusively, although God sees (Matthew 6:5-18).

How do we reconcile this not showing off with “letting our
light shine”?

One difference between the two situations is motivation. Why are we doing the good deed?  A wealthy person might give megabucks to fund a new building, but then perhaps, the person’s name appears in stone above the door.  Maybe a good test of our motivations is whether we would be as generous if our gift remained anonymous?

If motivation is different between the two sets of verses, what do they share? 

What’s similar about the passages is that they both express the primacy of our relationship with God.  The reward of the good works described in Matthew 6 is from God.  Likewise, when we let our light shine before others, it should be so that they see the deeds, and then praise God.

I remember a time I felt called to help a woman stranger in trouble.  (So you don't hear this as bragging, let me admit that I selfishly wondered what good I learned from it.)  In the course of our errands together, though, the woman asked me what church I belonged to, and called me “angel.”  Because the women was a stranger, she thought of the help as coming to her from God.   Only now, writing this study, do I realize its blessing in understanding Matthew 5:16!  But oh, it’s a scary thing to be viewed as God’s representatives!  It means that we absolutely have to try to “practice what we preach.”

But getting back to my own questions, I’ve also always been confused by the verse in Colossians (Col. 4:6) about our speech being full of grace, seasoned with salt.  One interpretation is that we should season our conversation in the world with our whole faith and personalities.  Thinking about which Christians have influenced me most memorably over the years, it isn’t just preachers in church; it’s living, breathing Joes and Josephines who can tell how God has sustained them in their own up-and-down lives.  It’s been a gift recently to be in a loose Bible study group where people do that.

For me, the summary seems to be this:  Respond to God first; be faithful in letting yourself be filled; live thankfully.  As a result, you will do things that help preserve this world, or certainly to improve its “taste.”  And, people will notice.   A city on a hill cannot be hidden, says Jesus, and maybe that’s my favorite image in the salt/light passage.
 
Build us as that city, Lord.

Or, make us the salt that spices.