"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 in the house." Matt. 5:13-15
Light, too, is in danger of becoming useless. Like salt, it can't lose it's essential nature. A hidden light is still light, but it is useless light. That's why people do not "Light a lamp and put it under a basket, but on a lamp-stand, and it gives light to all who are in the house." A light that is hidden under a basket can't even be used to read by; it helps neither the person who hides it nor anyone else.
Don't hide your light for fear of offending others, whether out of indifference or lovelessness or any other reason. If you do, you demonstrate unfaithfulness to the Lord.
(Daily Readings from the Life of Christ)