Maimonides writes:

There is a positive mitzvah to guard the Temple. [This mitzvah applies] even though there is no fear of enemies or thieves, for the guarding [of the Temple] is an expression of respect for it. A palace with guards is [much more impressive] than a palace without guards.1

When Maimonides mentions the “honor of the Temple,” he is referring not to the physical building, but to the presence of G‑d which resides there. This is in line with what he writes regarding the command to feel awe in the presence of the Temple: “It is not the [physical building of] the Temple which must be held in awe, but rather, He Who commanded that it be revered.”2

The same holds true when it comes to guarding the Temple: it is not the building itself which demands the honor guard, but the presence of G‑d which dwells there.

The Lubavitcher Rebbe, in a talk on Shabbat Parshat Shemini 5750 (1990), asked: Maimonides had previously established that the holiness of the Temple is not dependent on the existence of the physical building. The principle of “through its original consecration, it was consecrated for that time and for eternity (Kidsha le’shato ve’kidsha le’atid lavo)” applies. Meaning that the holiness of the Temple is present even today; it did not depart with its destruction.3 If this is correct, and we have established that the Temple guards were not there to guard the actual building, but to give honor to G‑d’s presence which resides there, then why is there no current obligation to guard the place where the Temple used to stand—Temple Mount?

Indeed, with regard to the obligation to be in awe of the Temple (as we referenced earlier), Maimonides explicitly states:

Even though the Temple is now in ruin because of our sins, a person must hold its [site] in awe, as one would regard it when it was standing.

[Therefore,] one should only enter a region which he is permitted to enter. He should not sit in [the area of] the Temple Courtyard, nor should he act frivolously when standing before [the place of] the eastern gate, etc.4

The Rebbe notes that there is indeed a halachic position that mandates that even today we should endeavor to post sentries at the Temple Mount, and Rabbi Hillel Moshe Meshil Gelbstein in his sefer Mishkanot L'Avir Yaakov has campaigned for this to happen. However, continued the Rebbe, the fact that this has not been taken up by any significant segment of the community seems to indicate that there is a valid reason not to.

The Rebbe therefore suggests as follows: One of the pervading principles governing Jewish law is derived from the verses in Leviticus, “You shall observe My statutes and My ordinances, which a man shall do and live by them.”5 In a case where one’s very life would be in danger while fulfilling one of the mitzvot, (with the exception of the three cardinal sins: adultery, murder, and idolatry,) one is not obligated to give up one's life in-order to perform the mitzvah.6

With this principle, the Rebbe suggests that the reason we do not post guards on the Temple Mount is simply because it is too dangerous. He goes so far as to say that in a case where there is possibility of death, even if death is by no means certain, still, one would not need to risk one’s life to fulfill a mitzvah. Even today, there would be an element of danger involved. Additionally, in the period directly after the destruction of the Temple it would have been extremely dangerous to physically guard the Temple Mount, “Once it was canceled it was not reinstated.” This follows a general halachic principle that once something is postponed or canceled it is not (necessarily) reinstated.7

Practical Application

In his unique style, the Rebbe points out that while the physical manifestation of this mitzvah seems not to apply today, the spiritual idea it represents is as valid as ever. He quotes the famous Midrash8 which elucidates the verse, “And they shall make Me a sanctuary and I will dwell in their midst.”9 From the strange language, “in their midst” (as opposed to in it [the Temple]), they explain that this verse teaches us that G‑d’s home is within each of us.

The Rebbe strongly encouraged each individual to create a ‘personal Temple’ in their home. When holiness pervades the home, it becomes a Temple for G‑d. This is how we are able to keep the spirit of the mitzvah of guarding the Temple alive. Through cherishing everything holy, through making the focus of our home the ‘personal Temple’ we create, we honor the glory of G‑d—the intent of the original mitzvah.