Matthew 5, 13-16:
13 "You are the salt of the earth. But if the salt loses its effectiveness, how can you make it salty again? It is good for nothing except to be thrown on the road and trampled underfoot by people.
14 You are the light of the world. A city located on a mountain cannot remain hidden.
15 You don't light a lamp and then put it under a bucket. On the contrary: you put it on the lamp stand so that it gives light to everyone in the house.
16 So let your light shine before men: they shall see your good works, and glorify your Father which is in heaven."