The Bible, the Book of Mormon, and other scriptural texts are full of symbolism that uses light. God is light and uses light; those who oppose Him work in darkness (see the links in this sentence for some examples). I've noticed a phrase that is used repeatedly in the Book of Mormon: "God worketh not in darkness." Of course, we are encouraged to emulate Him.
There are many ways to apply this idea. I'd like to focus on honesty and openness.