circumcision

Sefer Yetzira speaks of three dimensions: Olam, Shanah, and Nefesh.  Olam literally means "world" and signifies space. Shanah literally means "year" and signifies the dimension of time. Nefesh literally means "soul" and signifies the spiritual dimension. In another place, recognizing the space itself is three dimensional, Sefer Yetzira speaks of five-dimensional space which is a Minkowski spacetime with an addition of the fifth spiritual dimension. This construct is very similar to the Kaluza-Klein five-dimensional generalization of the General Theory of Relativity (a theory that is near and dear to my heart, because, unaware of its existence, I independently rediscovered it as a teenager.) Kaluza-Klein, first forgotten, is now experiencing a revival as a special case of the string theory. Sefer Yetzirah In every one of these dimensions, G‑d created the domain of holy [...]