Shevirat ha-Keilim

Here is how one Kabbalah site describes it:

However, the vessels could not contain these emanations, and in a cosmic catastrophe known as the Breaking of the Vessels, the vessels were displaced and shattered. The letters, which had been initially assembled into meaningful groups became a Babel of nonsense. This rupture in the universe created a separation of the opposites, in particular, a split between the masculine and the feminine aspects of both God and the Primordial Man.

The broken vessels tumbled down through the metaphysical void, trapping within themselves sparks of the emanated divine light.

And here is another:

Images of broken light which
dance before me like a million eyes
That call me on and on across the universe.
Thoughts meander like a
restless wind inside a letter box
they tumble blindly as
they make their way across the universe.