[G–d said to the Jewish people] “You shall have no other gods before Me.” Why was this said? Because G–d first said, “I am the L–rd, your G–d.” This is comparable to a king who entered a country. His servants told him, “Make decrees upon them.” He responded to them, “Only when they accept my sovereignty upon themselves can I make decrees upon them. For if they will not accept my sovereignty, they will not accept my decrees either.”Similarly, when G–d declared, “I am the L-rd, your G–d, Who took you out of Egypt,” the Jewish people accepted G–d’s sovereignty. Only once this basic submission to G–d had occurred were they able to then commit to follow the individual decrees that G–d then issued—the Mitzvos.
This explains why, according to one opinion, the declaration, “I am the L-rd, your G–d, Who took you out of the land of Egypt”—which commentaries interpret as referring to the imperative to affirm one’s core belief in G–d—is not counted among the Mitzvos. For the 613 Mitzvos are individual commandments. In contrast, the basic commitment to G–d is the all-inclusive foundation of all the Mitzvos. Since it enables one to keep all the Mitzvos, it cannot be counted as an individual Mitzvah.
This is also the meaning of the Jewish people’s declaration before the Giving of the Torah, “We will do and we will hear”:
In declaring “we will do,” the Jewish people submitted absolutely and unquestioningly to G–d’s sovereignty, affirming in a general manner that they would obey whatever G–d would command them, no matter what. At this stage, the actual details of the Mitzvos were not relevant.
But it is not enough to submit in a general manner. Thus, the Jewish people also declared, “we will hear.” Here they committed to hear in the sense of listening, turning their ears, and paying attention to the numerous minutiae of the Mitzvos.
Here we learn that Judaism is “in the details.” Jewish law is never vague. It clearly, methodically, defines the appropriate place and time in which every single Mitzvah is to be fulfilled. For instance, Tefillin must be square-shaped and black-colored, with certain kosher types of parchments and ink, which were produced by Jews with the intention of being used for the Mitzvah of Tefillin, and so on.
Being particular to learn and follow the details of Halacha is important not only in order to know how to submit to G–d, but also to enable the person to draw a flow G–dly light upon himself. Only when all the above criteria are fulfilled has the Mitzvah of Tefillin been performed, eliciting a divine light both in the supernal realms, and into the person wearing the Tefillin. The same goes for all the Mitzvos.
This is one of the reasons that the Mitzvos are compared to the organs of the body. The vitality of the soul only flows into the body when it is healthy and fit, and a wound or the like, G–d forbid, reduces or prevents that vitality from reaching the body. So, too, by performing Mitzvos a Jew serves as a vessel for G–dliness.
Moreover, these two levels of submission are interdependent. Only by undertaking to obey G–d’s every command, without any trace of reservation until he appreciates the reason, can he reach the level of focusing on the details of Halacha. Moreover, the more deeply felt one’s general submission, the more scrupulously he will pay attention to the minutiae of the Mitzvos as well, being particular to perform them all, even the often neglected ones, and in an attractive manner.
Adapted from the Previous Rebbe’s Reshimas Chag HaShavuos 5675, with references and explanatory notes from the Rebbe.
 Mechilta 20:3.
 Ba’al Halachos Gedolos.
 Bamidbar 15:41.
 Exodus 24:7. Shabbat 88a.
 See Tanya, ch. 23.