Part 13 · Chapter 116

Know that these ways are also the aspect of three Names of YHVH, and likewise in the manner that they are divided in the skull itself, and their fillings with Yods. There is also another reason why they were thirteen ways, and it is that their principal root is from Zeir Anpin, and it is known that they are the aspect of Vavs — the hooks of the pillars, as above — and Vav in its filling [spells Vav-Alef-Vav], which in gematria is thirteen. Therefore, corresponding to it, thirteen white ways came forth.