The Tetractys and the Sephiroth represent similar concepts; however the link between these two concepts would not be readily apparent were it not for their common use of the Tetragrammaton. The Tetagrammaton serves as a bridge between these concepts which span time, culture (Greek and Hebrew), and multiple Masonic rites and rituals. This paper discusses the Tetragrammaton, the Tetractys, and the Sephiroth and shows how the three are related.  […]

Source:  http://rosacruzes.blogspot.com/2009/02/tetragrammaton.html