The [consummate] revelation that “This is not a common place,” [that within the Beis HaMikdash will be a fusion of finiteness and infinity,] will be in the Third Beis HaMikdash. To explain the concept: The First and Second Beis HaMikdash [reflect] the four letters of the name Havayah (Y-H-V-H) which in turn allude to the Ten Sefiros. {The First Beis HaMikdash represents the first hei (Binah) [of that name] through which is revealed the yud (Chochmah). The Second Beis HaMikdash repre­sents the latter hei (Malchus) through which is revealed the vav (Zaer Anpin)}.1 The Third Beis HaMikdash represents the level of Keser, as noted above (sec. 3) that the “Lion will come” is the revelation of Keser that transcends the chainlike progression of spiritual existence.

Within the Ten Sefiros, the aspects of revelation and conceal­ment (oros and kelim, lights and vessels) function as two distinct entities. [The awareness that] both revelation and concealment are [merely] names of G‑d who transcends them both, is a result of the revelation of Keser that transcends the chainlike progression of spiritual existence.

[To elaborate on this point:] The distinction of the Sefiros [as separate entities] (Chochmah, Binah,...) is (primarily) relevant with regard to the revealed Sefiros of the realm of Atzilus. With regard to the Ten Concealed Sefiros2 of Keser, by contrast, all these different levels are united as one. Similarly, with regard to the distinction between the oros and the kelim (revelation and concealment), within the Ten Concealed Sefiros, they (the oros and kelim) are united.

Based on these concepts, it can be explained that the consummate revelation that ‘This is not a common place” will be in the Third Beis HaMikdash. [There it will be manifest] how space itself will serve as a receptacle for the revelation of that which is above space. For then it will be revealed within the names Havayah and E-lohim as they function within the chainlike progression of spiritual existence {and as a result, also in the two dimensions of transcendence and space, even as they exist within this physical world}, that they are both [merely] names of G‑d, who transcends them both, [and thus they] are truly one.

The above also enables us to understand the frequently made statement (cited above sec. 1), that the unique dimension of the Third Beis HaMikdash will be its eternality. On the surface, since the First Beis HaMikdash as well could have been eternal (as mentioned above ch. 3), why do we say that this is the unique dimension of the Third Beis HaMikdash?

It is possible to resolve the question as follows: The perpetuity that could have been manifest in the First Beis HaMikdash would have resulted (primarily) from the revelation of [the dimension of G‑dliness] that transcends time. The novel aspect of the Third Beis HaMikdash lies in the fact that, [in the Era of Redemption,] time itself will serve as a fit receptacle for this level,3 [i.e., that the dimension of timelessness will be revealed, not in contrast to the nature of the world, but in a manner that will permeate the nature of the world itself].

This is why the unique dimension of the Third Beis HaMikdash will be its eternality. For the true dimension of infinity (eternality) is that the eternality does not come solely as a result of influence from above, but that the lower level itself serves as a fit vessel for this. Eternality of this nature will be manifest only in the Third Beis HaMikdash.