What is the covenant of salt?

I am working on a scripture study activity over a couple days, but I have a simple precept to write about.

I learned about the covenant of salt, which I never was taught about before. It is very symbolic, yet is very real too. It is mentioned in the following verse:

"All the heave offerings of the holy things, which the children of Israel offer unto the Lord, have I given thee, and thy sons and thy daughters with thee, by a statute for ever: it is a covenant of salt for ever before the Lord unto thee and to thy seed with thee." (Numbers 18:19)

In the Old Testament we hear of prophets, numbering the minimum amount of saints required to preserve a nation from destruction. This is a tangible fruit of the covenant of salt. Abraham is known for negotiating with God about how many people were required to save Sodom and Gomorrah in Genesis 18.

"Salt has long been used to preserve, flavor, and purify... When salt loses its savor, it becomes ineffective, or “good for nothing” (Matthew 5:13). This happens when it is mixed with or contaminated by other elements. As disciples of Christ, we keep our “savor” by avoiding spiritual contamination from the world. This allows us to fulfill our preserving and purifying work as the salt of the earth—for example, through sharing the gospel and being an influence for good in the world (see D&C 103:9–10)." (Come, follow me)

The benefits of salt are a reflection of God's promises to preserving and purifying his covenant people. Salt pulling out flavor could represent the joy of the gospel. We truly have to work at the gospel to pull the joys of life to our taste. The gospel is not easy, but it is easier on man than life in the corrupt world.