More Salt, Please
I think one problem we might have with fully-understanding salt from a Biblical perspective is that for us, salt is so extraordinarily commonplace. I mean, it's everywhere, it's in everything, and it's relatively cheap. It seems, therefore, an insignificant thing. It connotes flavor, and that's about it.
But for people in Biblical times the word salt prompted a set of associations that were quite precise. Salt brought certain things to their minds that it does not bring to ours.
Here's an example. Let's take Paul's words in Colossians, "Let your words always be seasoned with salt." Now, for us moderns, salt is all about flavor. We can try to get our minds around Paul's idea of salt-seasoned words by reasoning, "Ah, so Paul must be saying that our words shouldn't be bland. After all, how could we ever hope to make disciples, how could we evangelize, if our speech is dull and insipid, lacking flavor?"
All well and good. But still we're missing out on the full range of Biblical connotation here. In those days, according to Smith's Bible Dictionary, there was something called a "covenant of salt." Such a covenant betokened "an indissoluble alliance between friends." This phrase, covenant of salt, turns up in 2 Chronicles 13:5, which says, "Do you not know that the LORD God of Israel gave the rule over Israel forever to David and his sons by a covenant of salt?"
Indissoluble. Get it? A bond of friendship that cannot be broken. These are some of the connotations, the aura of meaning, that surrounded the word salt for people in Palestine in Biblical times. And not only the Jews: for instance, the Bedouin (at least according to this website: "To the Bedouin the crime of bowqa or 'treachery' to a traveling companion - once you have 'eaten bread and salt' together as the saying goes - is an unspeakable disgrace."
Another modern example had historic implications. "When President Sadat of Egypt greeted Prime Minister Begin of Israel as he set foot on Egyptian soil, the two men stopped to take bread and salt together. They entered into a covenant of protection. Sadat was saying, by his actions, that Begin would be safe while visiting Egypt and that he was willing to guarantee that safety with his life." [This quote is from an online article entitled The Salt Covenant.]
So let us return to Colossians 4:6. "Let your words be always full of grace, seasoned with salt." Remember that in this passage Paul is speaking to church members about their relationships to those on the outside. Your words to them, he is saying, ought to carry with them the offer of friendship very much like God's to David. This is grace, and it is abounding grace. It has been poured out for us, so that we may abound in it toward others. Offering peace, this is what the covenant of salt is about, and that is what our words should savor of when we speak to outsiders. So that "thanksgiving may overflow, to the glory of God." (2 Cor. 4:15b)