Summary: Both salt and light: 1. Are necessary for survival. 2. Have the ability to purify. 3. Must make contact to have an effect.
I love grilling out on a beautiful summer day with the sun shining. My favorite thing is to grill steaks. I like to grill them till they are so tender you can pull them apart with a fork. Then I take roasting ears and dip them into water with the shuck still on; wrap them in foil and let the heat and steam do its magic. And what would a meal be without potatoes? Take them and wash them in fresh water, and then rub butter all over them; wrap them in foil and slap them on the grill. Shut the lid and let all that cook together, and the aroma of all that food cooking will drive you mad before you get it on the table. But now imagine one little thing missing — you don’t have any salt. The sizzling meat has no salt. The baked potato has no salt. And worst of all, the corn on the cob has no salt! And imagine one more little thing has happened. I started the process while it was light out, but by the time I was done it was pitch black out — and the electricity has gone off. We are sitting inside with food that has no seasoning, and now we can’t see it. It was a real good plan that went all wrong — just because there was no salt or light.
As early as the first century, Pliny wrote in his Natural History, “Nothing is more useful than salt and sunshine.” Jesus said, “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 by men” (Matthew 5:13). I questioned Jesus’ saying about salt losing its saltiness. Technically speaking, salt cannot lose its saltiness; sodium chloride is a stable compound. But in the part of the world where Jesus lived, salt was collected from around the Dead Sea where the crystals were often contaminated with other minerals. These crystalized formations were full of impurities, and since the actual salt was more soluble than the impurities, the rain could wash out the salt, which made what was left of little worth since it lost its saltiness. When this happened, the salt was thrown out, since it was no longer of any value either as a preservative or for flavoring.
Jesus was warning against the danger of our lives becoming contaminated and thereby becoming of no value for the kingdom. The actual word he uses for salt becoming “tasteless” is the Greek word moraino. It can mean “foolish” and is the word from which we get the word “moron.” He was saying that salt losing its flavor and becoming insipid is a picture of what it is like when a Christian loses his or her influence in the world. Their lives become contaminated with impurities and they become foolish. The Expositor’s Bible Commentary explains: “The point is that, if Jesus’ disciples are to act as a preservative in the world by conforming to kingdom norms, if they are ‘called to be a moral disinfectant in a world where moral standards are low, constantly changing, or non-existent. . . they can discharge this function only if they themselves retain their virtue’ (Tasker).” Christians are to permeate their culture as agents of redemption, and when they fail at this, it is a major error. It damages the individual Christian and impoverishes the world. The people of God are what preserve the world and give it flavor. So either we become good salt, or we are insipid and useless, and are cast out — not of benefit to anyone.