13 “You are the salt of the earth. But if the salt should lose its taste, how can it be made salty?[a] It’s no longer good for anything but to be thrown out and trampled under people’s feet. (Matthew 5:13 CSB)
We know salt as a seasoning. Back when the Bible was written it was also a preservative. Thus, slat was useful on multiple levels. The same holds true with our ministry to others today. In some cases it is used to season and in other cases to preserve.
But if we do not remain in Christ our faith loses its flavor. It becomes weak and useful for little other than to preserve us.
Thus, we are to remain salty in our faith so that we can be the flavor and preservative in others lives.