Salt is a wondrous combination of two things — sodium and chlorine — that are dangerous and poisonous on their own. It’s important enough to life and history that Mark Kurlansky wrote an entire book about it (highly recommended).
But salt’s goodness has limits.
A little bit of salt enhances a dish. Too much salt ruins a dish: It no longer tastes like the dish it was meant to be; it only tastes like salt. When it comes to salt, moderation makes it more effective and saturation makes it unpalatable.
(Image: “salt,” by Stock Catalog, on Flickr under Creative Commons.)
Those of us who are Christians should bear that in mind. Christ’s words to the disciples hold true for us, yes: We are — not should be, not could be, but are — the salt of the Earth. And we should take care to retain our saltiness, lest we be good for nothing. But our job is not to preserve things as they are, to keep them from rotting; it’s to improve things, to make them better than they were before and even better than they are on their own. We should take care to flavor the world, not to ruin it by dumping bucketfuls of our otherwise beneficial salt on everything in sight.
by 
