It’s a question that takes us deep into the heart of Kabbalistic thought, specifically concerning the structure of the Sefirot, those divine emanations through which God manifests the universe.

To understand this, we need to talk about Bina, often translated as Understanding. In the Kabbalistic Tree of Life, Bina is a crucial Sefirah, sitting high up, just below Keter (Crown) and Ḥokhma (Wisdom). Bina is all about comprehension and giving shape to the raw potential of Ḥokhma.

Now, here's where it gets interesting. Bina has two sides, a right and a left. Think of them as two channels. According to the Sulam Commentary, the right side of Bina is associated with lights of giving, of bestowal. The left side, on the other hand, is associated with the lights of Ḥokhma, of wisdom.

So, what happens when these lights are distributed unevenly?

Well, Ze’er Anpin, often referred to as the “Small Face” or the “Son,” receives the light of giving from the right side of Bina. But, crucially, it receives this without the light of Ḥokhma. Simultaneously, the Nukva, the feminine aspect or “Daughter," receives the light of Ḥokhma from the left side of Bina, but without the light of giving.

Why is this a problem? Because, as any good Kabbalist will tell you, Ḥokhma cannot truly shine, it cannot illuminate, without the light of giving. It’s like having a brilliant idea but no way to express it, no way to bring it into the world.

The result? The Ḥokhma received by the Nukva becomes "frozen." It becomes darkness instead of light. The Nukva, in this state, struggles to sustain itself.

This, the Sulam Commentary explains, is the mystical meaning behind the moon’s complaint: "Two kings cannot use a single crown." What’s this all about?

Well, Bina, at this level, acts as Keter – the Crown – for both Ḥokhma and giving. It’s the portal through which these higher, supernal lights flow. But when both Ze’er Anpin and the Nukva try to draw from this single source unevenly, Ze’er Anpin ends up with pure giving, lacking wisdom, and the Nukva ends up with pure wisdom, lacking the ability to give. And that imbalance leads to…darkness.

The Nukva, representing the receptive, feminine principle, simply cannot withstand that state of isolated, unexpressed wisdom. It needs the balance, the interplay of giving and receiving, to truly shine.

So, what does this all mean for us? Perhaps it’s a reminder that true illumination comes not from hoarding knowledge or giving without intention, but from finding that delicate balance, that beautiful interplay between wisdom and compassion. It's in the sharing, in the giving of ourselves, that we truly bring light into the world, and avoid the darkness that comes from imbalance.