There is an old custom to have salt on the Shabbat table. Some people confuse this custom with a different custom of dipping your challa in salt, which comes from a time when people made their challah without salt. If you've ever forgotten to add salt to your challah, then you know where that custom comes from.
But the custom of having salt on the table is derived from the Temple, where salt was used and eaten with the offerings, where it's proscribed as "the salt of God's covenant". What is the covenant of salt?
During the six days of creation - recounts the Midrash - when the "waters above" were separated from the "waters below" the lower waters protested that they were now very lowly and far from God. So God promised them that they would be elevated by humanity. How do we get sea salt? We boil water - thus, even the water gets elevated, leaving only the lowly salt down below. The "covenant of salt" therefore teaches that we should look for spirituality in all parts of creation, not just the obviously "holy" things and activities.
Ask at your table: What is an activity that most people don't consider spiritual? How could you turn that into a spiritual activity?
Bonus - make your own challah: Since we began with challah, I would like to share with you the recipe for my wife's famous challah (in her humility she claims she cribbed the recipe from her friend Tal). She claims that it is easy to make. All I know is that it is easy to eat - so much so that I have to remove it from the table lest everyone fill up on challah and not have room for the rest of the meal.
2 cups water, 1 TB dry yeast
3/4 or so vegetable oil
3/4 cup sugar
about 2 cups whole wheat flour
ADD 1 TBSPOON SALT AT THIS POINT
add white flour (about 5 cups) until consistency is right (not sticking to fingers)
Let rise until it doubles in size
Punch, braid, let rise another while, then bake at 350 until brown.
(I've never made this recipe but have learned over the years how to tell when it is done by the smell - when the whole house wafts with an enticing smell, it's about done)
How to eat challah:
King Solomon decreed that we should have salt on our Shabbat table in order to make our table a symbolic altar. Like the priests, we wash our hands with a washing cup, dry them and then don't speak until Hamotzi. The one making Hamotzi holds the 2 challas with all ten fingers, to have in mind the 10 labors required to turn a wheat seed into bread and the 10 words in the bracha (BARUCH ATOH A-DONOI E-LOHAYNU MELECH HA-OLAM HA-MOTZI LECHEM MIN HA-ARETZ)....remember "Eeny-Meeny-Miny-Mo" from a few weeks ago?