"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 who are in the house. Let your light so shine before men, that they may see your good works and glorify your Father in heaven." (Matt 5:14-16).
We all understand that light here means good works and we are meant to do good works that will bring glory to God. However, we must be very careful that when we go about shining the light we don't end up shining a light that is based on the tree of the knowledge of good and evil. The only light that will bring life to this dying world is that which is Christ.
"In Him was life, and the life was the light of men. And the light shines in the darkness, and the darkness did not comprehend it." (John 1:4,5).
If the light based on the tree of the knowledge of good and evil can do any significant good in this world God would not need to send Jesus into this world. Most often when talking about shinning the light Christians feel that since it means good works then they could just go about doing whatever they feel is good. No, it is not about what we think is good, it is rather about what is Christ. For God is only satisfied with that which is Christ. He is well pleased with this Christ and this Christ alone.
No amount of "good" will truly please God or bring glory to God. This light is now a person; it is not just anything that we feel is good. This person lives in us and until you are awakened to this living light you will never be able to truly shine him. This light is Lord, we are not the ones that dictate how he should shine. No, he is the one that decides how he wants to shine. You must be awakened to this light in you, and you must be able to receive instructions from him and detect how he wants to shine.
You must rest in this light, pay attention and listen carefully to detect what he wants and how he wants to express himself. He is Lord so yield to him. Surrender to his grip, let him have you and use you to express himself. No the light is not your instrument, you are his instrument, for he is the one leading. Submit and let him lead, that is the only way to truly shine the light that brings life — a light that shines and darkness could not comprehend it.