Light is an apt metaphor for God, a metaphor central to the thinking of Archbishop of Canterbury Rowan Williams.
Physicists do not understand light, which has properties associated with both particles and waves. Theologians (and everybody else!) do not understand God.
Light enables human life, infusing our world with beauty, enabling visual perception, warming and fueling human existence. God does the same.
Carolina has distinctive deep blue skies. Giverny, France, where Monet painted, has an opaque light, equally distinctive not only in Impressionist painting but also when experienced in person. Hong Kong (and many other places) often has a gray light, full of pollutants. I understand how humans can alter light, both for the bad and for the good (the shutters I have installed on my home windows create a light evocative of that in Giverny).
Humans experience God in a variety of ways. Sometimes, the experience of God seems to have more to do with human causes than with God, e.g., in a loving community. Sometimes human actions can obscure God, e.g., the Holocaust. Yet human experience seems to have an intrinsic element of mystery, of something that is greater than finite humans are, even as Carolina skies and Giverny mornings can evoke a similar awareness.
In what ordinary moments do you experience that which transcends the finite, that which is the holy, the ultimate?