Luke 8:16-18 "No one would light a lamp and then cover it up or put it under a bed. No, lamps are mounted in the open where they can be seen by those entering the house. For everything that is hidden or secret will eventually be brought to light and made plain to all. So be sure to pay attention to what you hear. To those who are open to my teaching, more understanding will be given. But to those who are not listening, even what they think they have will be taken away from them."
The purpose of lamps is to dispel darkness. They are there to guide through the darkness. They are there to protect us from getting hurt by things we might not otherwise see. They give understanding of those things which are around us. Lamps that are not functioning as lamps are not useful as lamps.
Lamps illuminate and applied spiritually means that what is in the soul will be revealed. For some, their day of revealing is going to be much sooner than expected. For others it won't happen until Jesus comes back to earth to take those who have a pure heart home to heaven with Him.
God illuminates the soul through Christ and His Word. We must pay attention to them so that we will have proper understanding of God and His ways. No one can understand spiritual truths apart from the illumination of the Holy Spirit on the soul. All who listens and believes will be given much understanding. For all who don't listen what they may have will taken away from them. This means that sin darkens the soul and what little understanding one may have will be squelched by sin and taken away from the listener.
Keep your light lit and shining brightly for all to see and never let it go out.