Editing Ohr Ein Sof (section)

==== Light Contained Within the Essence ====
The Infinite Light—both the essence of the light and its extension and revelation—is contained within the Divine Essence. Therefore, they have no independent existence at all. Since nothing exists outside of Him, wherever the light shines and is revealed, it remains contained within His Essence. Just as the sun's light, when still within the sun itself, has no independent existence but is merely the potential to illuminate, so too the light has no sense of independent existence but is completely nullified to its source, being nothing more than the Divine Essence's power and capability to shine light.

Only after the Tzimtzum does the possibility arise for the light to sense its own existence as if emerging from the existence of its source. Before the Tzimtzum, the entirety of the light was contained within the Divine Essence.

The nullification of the light within the Divine Essence is deeper than the nullification of sunlight within the sun's orb:

A. The nullification of sunlight within the sun applies only to the essence of the light contained in the sun, not to its revelation and extension, which exist outside the sun and are not contained within it. In contrast, even the extension and revelation of the Infinite Light before the Tzimtzum are contained within the Divine Essence, nullified, and without independent existence.

B. The "manner" of nullification of sunlight differs from that of the Infinite Light. Sunlight within the sun is the "power of light," whereas the contained Infinite Light is the "capability" of the Divine Essence to illuminate. (The difference between "power" and "capability" is that power is considered the beginning of something. That is, the thing already exists in reality (since power is power for something specific and already has a certain characteristic), but is still concealed within its source. In contrast, capability does not represent the beginning of the thing, as it relates to the one who is capable—that he can do as he wills (and his capability is not yet formed into the thing he will do)—rather than to the thing he is capable of doing. Therefore, power is considered the beginning of something's existence, whereas capability is not.)

The reason for this is that we see the sun is compelled to produce light, which necessitates that the concept of light already exists in reality before its actual revelation. In contrast, since the Divine Essence is not compelled to produce light at all, and its revelation is by will (as will be explained at length), it follows that the power to illuminate contained within the Essence is not the existence of light, but rather the capability to illuminate.

Additionally, the Divine Essence has no intrinsic purpose of revealing light, so we cannot say it has the power to illuminate. This differs from the sun, whose purpose is to illuminate, meaning light is within its nature and exists within it in a concealed state.