Matthew 5:13-16 

13 You are the salt of the earth. But if salt has lost its saltiness, how can it be made salty again? It has become useless. It can only be thrown away and people will trample on it.

14 You are the light of the world. A city built on a mountain cannot be hid den.

15 No one lights a lamp and covers it; instead, it is put on a lamp stand, where it gives light to everyone in the house.

16 In the same way, your light must shine before others, so that they may see the good you do, and praise your Father in heaven.