I personally try not to assign any "ism" to my truths. I do, however, tend to cherry pick truths from all religions, weaving a silver line that runs through them all.
I think revsdd is correct, the physical Sun by it's very existence heat and light.
The real secret to understanding this analogy, of the Sun symbolizing a regent and physical presence of God, is best seen, I believe, when one first studies their own micro natures. "Man, know thyself" speak one oracle of history, and "the truth lies within" says another. Only then, when we apply those micro observations of ourselves to the greater Macrocosmic Whole, can we turn one of the secret keys of Life, that deep mystery, the mystery of the greater Macro Life Whom we call, for lack of a better term, "God".
If we are to believe that we ourselves have a physical side of form and matter and a formless and spiritual side, then it would stand to reason that the Sun too, in a much higher turn of the wheel, would also have a spiritual and invisible (from our point of view) aspect to It's Being.
The Sun is much like an electron, but on a much larger scale. It is pure energy with a nebulous but physical form. And energy is the closest thing we could ever appropriate to "God" in the physical world. Energy is what ties the formless spiritual to form of matter
"God is a consuming fire" says the Old Testament, and "electricity" is the highest form of matter says the new age tenets. The energy of all physical matter is made up of nothing but positive, negative and neutral electrical forces. Matter is like frozen but pliable energy, as it is constantly moving and changing form. The forms themsleves are temporary and ephemeral in nature. Yet at the atomic level, the same trinity of forces, the positive, negative and neutral particles that make our physical world, are the same particles that have been around since the creation of time and space. They are relatively eternal in nature.
If Arianism believes the Sun to be the body of God, then I agree. As the Bible says "we live and move and have our being" within the body God. This is a physical fact and a very ancient concept. But the Sun is still only the lowest aspect of a stupendous energy, an energy that is reponsible for all life within our Solar System as it works it 's way from the Spiritual into physical form.
Within the heart of our Physical Sun lies an even greater Spiritual, or Central Sun. And that sacred Heart Central is Itself part and parcel of a Greater Heavenly Man, stretching out across space. In our Father's house there are many mansions.
We, as human beings, are microcosms within the body of this great Macrocosm. We too, as human beings have a spiritual centre with our hearts. In this way we are made in the image of God. It's in our growing awareness, I believe, that we become like unto God. First by becoming aware of "the tree of good and evil", e.g. the pairs of opposites of positive and negative where rational thoughts, discerning between good and evil, starts us on our long journey home. And secondly, and eventually, we discover the Christ Consciousness within, that is the Christ Awareness within that joins the two opposites of Spirit and matter. It's the force of equilibrium that connects the yin and yang, making them One.
Such are my ponderings.