Fear is because of ignorance or lack of understanding of the reality. We fear a certain object until we know about it. Once we know about it, we have no fear. Suppose one rainy night when you take a walk in the woods, and find a long object lying across on your way. You would fear whether it is a snake. With the fear you would not proceed further and may even turn back and go the way you came. But once you shed light from your torch on the object and find out whether the long object is a snake or just a rope , your fear is gone.