In his early remarks during what we call the Sermon on the Mount, Jesus describes His disciples as “the salt of the earth.
13 “You are the salt of the earth; but if the salt has become tasteless, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled under foot by men.”
Jesus takes it for granted that all understood the uselessness of salt that is incapable of preserving and flavoring. “Throw it away!” is His advice for useless salt. The application to Christians is clearly seen. God put us here to preserve and flavor His world. If we are not doing that, what good are we to Him or others?
In A.D. 252, a killing plague swept through the North African city of Carthage. The heathens threw the dead in the streets and fled the city in fear for their lives. Cyprian, leader of the church in Carthage, marshaled the saints and they began burying the dead and nursing the sick. Their action saved the city and thrust the church into prominence in the minds of its citizens.
Good people are salting the earth and preserving the creation of God. They are lighting the world and glorifying the God who made it.