Read Matthew 5:13-20
13 “You are like salt for the whole human race. But if salt loses its saltiness, there is no way to make it salty again. It has become worthless, so it is thrown out and people trample on it.
14 “You are like light for the whole world. A city built on a hill cannot be hidden. 15No one lights a lamp and puts it under a bowl; instead he puts it on the lamp-stand, where it gives light for everyone in the house. 16In the same way your light must shine before people, so that they will see the good things you do and praise your Father in heaven.
17 “Do not think that I have come to do away with the Law of Moses and the teachings of the prophets. I have not come to do away with them, but to make their teachings come true. 18Remember that as long as heaven and earth last, not the least point nor the smallest detail of the Law will be done away with—not until the end of all things.a 19So then, whoever disobeys even the least important of the commandments and teaches others to do the same, will be least in the Kingdom of heaven. On the other hand, whoever obeys the Law and teaches others to do the same, will be great in the Kingdom of heaven. 20I tell you, then, that you will be able to enter the Kingdom of heaven only if you are more faithful than the teachers of the Law and the Pharisees in doing what God requires.
You are the salt of the earth.