In the bible, Matthew 5:13-16 talks about salt and light. Jesus is using these two things to show us how we should act.
Matthew 5:13-16 says
You are the salt of the earth; but if the salt loses its flavor, how shall it be seasoned? It is then good for nothing but to be thrown out and trampled underfoot by men. You are the light of the world. A city that is set on a hill cannot be hidden. Nor do they light a lamp and put it under a basket, but on a lampstand, and it gives light to all who are in the house. Let your light so shine before men, that they may see your good works and glorify your Father in heaven.
When Jesus says ‘we are the salt of the Earth’ he is saying that we are cre-ated to show the love of Christ through good deeds. He has used salt to show that we need flavor in ourselves and that we can use salt to influence others. Where there is anger, we can make peace, where there is sorrow, we can make happiness with the salt we have. When someone has no salt in them it will make them worthless and good for nothing.
In verse 14, Jesus starts to talk about light. He has used light to show that we should spread our brightness. By saying brightness, Jesus means that we should shine before men just like it says in verse 16. In these four verses, Je-sus is saying that we should be an influence to others and also shin our light to others and God.