Have you ever shined a flash light during the day. It doesn't do much, does it? But turn on the same light at night and it makes a huge impact. If, as Christians, we only "shine our light" to other Christians, yes we will still be a light, but nothing compared to if we shine our light into the darkness.
Jesus associated with the tax collectors, lepers, prostitutes, and sinners. He shunned the pharisees (religious leaders) of his day. He offered salvation to all, and loved us while we were still sinners.
My world is small, and I am surrounded by light. It is easy to shine in this environment. Am I courageous enough, and relevant enough, to dare to face the darkness, and shine my light there? Are you?
You are the light of the world. A city on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before men, that they may see your good deeds and praise your Father in heaven. Matthew 5:14-16