Before creation as we know it, there was only the Eyn Sof, often translated as "the Infinite" or "Without End," God in an utterly boundless state. Think of it as pure, unadulterated potential, filling all space. But how does something infinite give rise to something finite, like our world? That's where the concept of Tzimtzum comes in.

Tzimtzum (Hebrew for "contraction" or "self-limitation") is the idea that God, in a sense, contracted or withdrew from a certain "space" within Himself. This wasn't a physical shrinking, mind you, but a metaphysical one, making room for creation. It's a mind-bending concept, I know!

So, what was left in this newly "emptied" space? According to Kalach Pitchei Chokhmah (a key text of Kabbalah, literally "The 26 Openings of Wisdom"), the answer is a special kind of light. This light wasn't the Eyn Sof itself, but a "Residue of the Primordial Light." Think of it as an echo, a faint glimmer left behind after the infinite light withdrew.

Now, here's the kicker: this "Residue" was so incredibly potent that it, too, was almost impossible to grasp. It was, in its own way, still too much for finite beings to comprehend directly. Yet, paradoxically, this Residue became the very foundation for everything that exists.

Why? Because, as Kalach Pitchei Chokhmah explains, this Residue "is called the Place (or Space) of all that exists, because this is what gives them the ability to exist, which the aspect of limitlessness did not give them." The very act of contraction, of creating a defined space, allowed for the possibility of boundaries, of individual things taking shape. The infinite, by its very nature, couldn't provide that.

This "place or space" is described as "empty," but not in the way we usually understand emptiness. It's not devoid of God entirely, but rather devoid of the limitlessness of God as it was before the Tzimtzum. It's a subtle but crucial distinction. It’s like saying a canvas is empty before the artist paints on it – it’s full of potential, waiting to be filled with form and meaning.

So, this Residue of Light, born from the divine contraction, becomes the stage upon which all of creation unfolds. It's the hidden foundation upon which our entire reality is built. It raises the question: can we ever truly understand the depths of what came before creation, or are we forever looking at reflections of reflections? And what does this tell us about the nature of reality itself?