If you observe carefully the thoughts of your own mind, you can recognize that there is a spiritual light completely distinct from physical light. When a mind is thinking, it sees its objects in light, and people who think spiritually see truths as readily at midnight as in daytime. This is why we attribute light to our discernment and talk about “seeing.” One person may hear what someone else says and say, “I see that this is true,” meaning “I understand.” Since this understanding is spiritual, it cannot see by physical light. Physical light does not last, but departs with the sun. We can see from this that our discernment enjoys a light other than that of our eyes, and that this light comes from a different source.
Take care not to think that the spiritual world’s sun is actually God. The real God is a person. The first emanation from his love and wisdom is something fiery and spiritual that looks like a sun to angels. When the Lord makes himself visible to angels in person, then, he does so in human form, sometimes within the sun, sometimes outside it.
It is because of this correspondence that in the Word the Lord is called not only the sun but also fire and light. “The sun” refers to him as divine love and wisdom together; “the fire” refers to him as divine love, and “the light” refers to him as divine wisdom.
from Divine Love and Wisdom, Sections 96-98