'God' and 'light' are two concepts that are closely intertwined. Any kind of depiction of God usually includes a radiating source of light.
Even physical light has interesting properties. On the level of quantum physics, light sometimes behaves as a wave, and sometimes as a particle. This dual nature points to not that something is wrong with light, but that our understanding of it is deficient. Another fun fact about physical light is that it moves at the speed of light, and the theory of relativity points out that at the speed of light time as we know it doesn't exist - for light, everywhen is NOW.
Light in the metaphysical sense is also interesting. When someone is closer to God, we say that person is 'enlightened'. An insight can strike as lightning, and a good idea can feel like a light bulb has been turned on inside our minds. Light in this sense is definitively associated with a higher state of mind.
Matter as we know it may also not be much more than light circling into itself. We might say that light is a primary emanation of God in the realm of this world. Many traditions and beliefs associate the Sun with the creator aspect of God for this reason.
The opposite of light is not darkness - it's also light. Light can reinforce itself or align back to nothingness. Therefore parallels can be drawn between light, Love, and God: the opposite of Love is also Love, and the opposite of God is also God. Everything is integrated into unity, and all is one!