Light permeates us. Light is one expression of the essence of all things. I radiate light. All beings radiate light. Richard Bach, in Jonathan Livingston Seagull, wrote that more important than having faith was having imagination. Imagination is a catalyst for all things. Imagination calls forth reality. When you imagine light radiating through you you bring that light forth.
We are not empty vessels and therefore our light tends to become obscured. Spiritual light, unlike every day light, however, permeates all things. It can be obscured only when that which is permeated rejects the light, creating areas of darkness. We reject the light with shame, anger and coldness. We forget that our essence is light. We accept dark things as our lot. We may even feel more comfortable in the dark. We may be so convinced of the beliefs permeating our darknesses that we become ashamed of light, of shining. "How can I shine when I am so worthless?" and "I'm so unhappy with the way things are, I absolutely will not be happy!". While we usually do not actually think such thoughts, such stories dwell in our world of feeling, guiding our attitudes.
Imagining light radiating through you brings forth that light. Light seeps into the dark areas. Light radiates out of you. Light radiates into you.
Imagining light radiating through other beings brings forth that light. Light surrounds them. Light seeps through the cracks in their disbeliefs. Light beckons to them.