Part 2: The entire structure is built on this foundation… namely on the oneness and unity that we have explained.
The entire structure refers to all that was brought into existence by God, including both the lights (אורות, Orot, the Sefirot) and the separate realms and beings (נמצאים נפרדים, nimtza’im nifradim, the worlds and creatures that derive from and are governed by the Sefirot). This entire structure is founded on unity, in the sense that it is a single, complete entity that manifests the truth of this oneness and unity in the parts of the structure itself. The lights (Sefirot) that may be seen in it, the “bodies” (the created realms and beings) that exist in it, how they are governed and all that happens to them – all were made as parts of a single order which points to and actively reveals the underlying oneness.