The radiance emitting from the ark is said to be the Shechinah, or G-d dwelling within the ark. I like to think of it as G-d’s energy.    

Shechinah 

(; lit. "the dwelling"): 

Shechinah שכינה is derived from the word shochen שכן, “to dwell within.” The Shechinah is G‑d as G‑d is dwelling within. Sometimes we translate Shechinah as “The Divine Presence.”

The majestic presence or manifestation of God which has descended to "dwell" among men.

The word Shechinah is feminine, and so when we refer to G‑d as the Shechinah, we say “She.” Of course, we’re still referring to the same One G‑d, just in a different modality.

The term was used by the Rabbis in place of "God" where the anthropomorphic expressions of the Bible were no longer regarded as proper (see Anthropomorphism). The word itself is taken from such passages as speak of God dwelling either in the Tabernacle or among the people of Israel.

After all, you were probably wondering why we insist on calling G‑d “He.” We’re not talking about a being limited by any form—certainly not a body that could be identified as male or female.

Remember the 13 attributes of G-d.

G-d is Incorporeal

Although many places in scripture and Talmud speak of various parts of G-d's body (the Hand of G-d, G-d's wings, etc.) or speak of G-d in anthropomorphic terms (G-d walking in the garden of Eden, G-d laying tefillin, etc.), Judaism firmly maintains that G-d has no body. Any reference to G-d's body is simply a figure of speech, a means of making G-d's actions more comprehensible to beings living in a material world. Much of Rambam's Guide for the Perplexed is devoted to explaining each of these anthropomorphic references and proving that they should be understood figuratively.

We are forbidden to represent G-d in a physical form. That is considered idolatry. The sin of the Golden Calf incident was not that the people chose another deity, but that they tried to represent G-d in a physical form.

G-d is Neither Male nor Female

This follows directly from the fact that G-d has no physical form. As one rabbi explained it to me, G-d has no body, no genitalia, therefore the very idea that G-d is male or female is patently absurd. We refer to G-d using masculine terms simply for convenience's sake, because Hebrew has no neutral gender; G-d is no more male than a table is.

But consider this: As soon as we just begin to refer to G‑d, we have already compromised His oneness. Because we have already created a duality—there is us and there is G‑d. In that duality, we take the female role, so that He calls us She and we call Him He. Then we do whatever we can to mend the schism between us and return to one.

How the Shechinah Was Exiled

You may have heard of the primordial disaster, a creation narrative first told by Rabbi Yitzchak Luria, known as “the Ari.” The narrative is told in dazzling, spectacular metaphor, fit for a grand eye-candy sci-fi movie. But it is all metaphor. Metaphor of a reality no human being could ever imagine. And so it is told in these fabulous terms:

Prior to the creation of our chain of worlds, another order was first created, that of Tohu. Tohu was the first example of planned obsolescence: it was designed to fail. Tohu is the source of every type of passion and desire that has the potential to destroy everything in its wake, including itself. It was designed with absolute intensity, so that the energy it contained would be in complete conflict with the vessels its energy entered. And so, Tohu brought about its own destruction.

But for a purpose.

From that initial catastrophe, the highest sparks fell to the lowest places. Think of an explosion: Those elements upon which the greatest force is exerted will fly the furthest from the core of the explosion. Which tells us that to find the most powerful remnants of the essence-light of Tohu, we need to journey to the lowest of the worlds that explosion generated.

Could this be the big bang that many scientist talk about in reference to the creation of the universe?