Following the events of the Korach episode, the Torah clearly delineates the role of the Kohanim and Leviim. Although they participated in different ways in the service of the Mishkan, they are both given the mitzvah of Shemiras HaMikdash - the guarding of the Mishkan, and in subsequent years, the Beis HaMikdash. There are two reasons for this mitzvah. Rashi (Bamidbar 18:2) focuses on the practical goal of guarding the Mishkan in order to prevent a non-Kohen from entering. By contrast, the Rambam (Hilchos Beis Habechira 8:1) highlights that guarding is not for any practical concern, but rather, it is an expression of honor for the location. The Rambam compares this to a palace that is guarded simply as a sign of respect.
Shemira - guarding - plays an important role in many areas of mitzvah observance. There is an obligation to institute safeguards to protect the mitzvos. This requirement is derived from the wording of the Torah, "You should guard my precepts" (Vayikra 18:30). Guarding the mitzvos by instituting rabbinic prohibitions accomplishes two things. On a practical level, it prevents one from violating a Torah prohibition. By not moving a pencil on Shabbos, one will most likely not come to write. But rabbinic restrictions also accomplish another goal. By observing these additional protective measures, we demonstrate our reverence for the Torah laws. Just as the palace of the king must be guarded as an indication of honor and respect, so too, do the mitzvos warrant our recognition of their significance.
Although all of the mitzvos require protection, the mitzvah of Shabbos is unique in that Shabbos observance is described as "guarding the Shabbos." In the realm of hilchos Shabbos, there are numerous rabbinic prohibitions. These serve not only to prevent actual Shabbos violation, they also serve to elevate the significance of Shabbos in our eyes. It is precisely because Shabbos is such a precious treasure that we must guard it by meticulously observing every rabbinic safeguard.
The Torah speaks numerous times about guarding and performing the mitzvos. Chazal interpret guarding as referring to talmud Torah. Studying Torah serves a dual function as a guard for Torah observance. First, Torah study lends to practice in a direct manner; one who is not knowledgeable about the intricacies of mitzvah observance will not be able to properly perform the mitzvos. Torah study also indicates our appreciation of the mitzvos. Chazal compare the words of Torah to a King's decree. One who analyzes and reviews every nuance of the King's word is showing the proper reverence for the King. Similarly, our involvement in Torah study is an expression of honor and respect for Hashem's Word. By studying Torah, we are guarding our most precious treasure.
We have been entrusted by Hashem with many gifts. Mikdash, Shabbos, Torah and mitzvos must be guarded as they are our most sacred possessions. By according them the utmost honor and respect, we show true reverence for Hashem Who bestowed these treasures upon us.
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