One of the most ancient debates about Jewish thought revolves around the tension between two radically different experiences and understandings of our religion. On the one side stand the mystics, who see everything in this world as having cosmic significance. For them, Hashem is constantly sending us messages. If it rains on Sukkos, it must be because Hashem is displeased with us. Nail clippings should not be left around lest a pregnant woman step on them and miscarry. Weddings should take place on Tuesday because on the third day of creation, the Torah says טוב" כי" twice, and the beginning of the month of Av is a very bad time to do business or travel.
In the other corner stand the pure rationalists, for whom strict observance of Halacha is the only relevant fact. Is it forbidden or permitted? Did I eat enough Matzoh to technically fulfill the Mitzvah or not? Does my Kiddush cup hold the requisite amount of wine? Does it make a difference whether I say אמן using Sephardi or Ashkenazi pronunciation? For them, Judaism is not a set of messages that we receive from up above, but a set of requirements and obligations imposed upon us. Two Mitzvos in this week's Parsha seem to legislate against either extreme, nudging us toward some middle path.
Toward the middle of the Parsha, the Torah warns against all sorts of fortune telling or soothsaying (ויקרא י"ט:כ"ו, ל"א). Whether we theoretically have the capability to do so or not, it is not our place to interpret events in the world as Divine signs or omens. What Hashem does is His business; superstition is off limits. To suggest that we can understand why a group of schoolchildren on a bus in Eretz Yisrael or in a day care center in Oklahoma were killed, aside from being arrogant, is strictly forbidden. "השמים שמים לה'" - Heavenly decisions are for Him alone to understand; "והארץ נתן לבני אדם" - all we can do is react in ways that make sense in the earthly world which we live in )עיין תהלים קט"ו:ט"ז(.
On the other hand, the Parsha opens with a command whose parameters are so broad that they encompass nearly every facet of religious, personal and communal life - קדושים תהיו, be holy people (ויקרא שם פסוק ב'). In perhaps his most famous piece of commentary, the Ramban (שם) illuminates the concept of Kedushah, holiness. Kedushah is not a function of self-denial or meditation on a mountain-top. The Mitzvah of קדושים תהיו is the imperative to go beyond the question of "What is required or forbidden?" and explore the question of "What is appropriate or inappropriate?" Holiness means being concerned with more than merely the requirements to fulfill the technical obligations of Mitzvos and the strict avoidance of violations of Aveiros. קדושים תהיו demands that we begin to investigate the essential message of the Mitzvos, find the ethical principles driving the machinery of Halacha, and apply those principles in ways that far exceed the narrow boundaries of the "four Amos of Halacha."
The juxtaposition of these two opposite Mitzvos at the beginning and end of the body of commands in this Parsha leads to some challenging speculation. First, the Torah is warning that rigid "Halachism" can be as dangerous and flawed as ethereal mysticism. Second, it is critical that we find a balance between these two polar extremes. It is that balance that needs to be reflected through the prism of all the Mitzvos described between these poles - Mitzvos identified as being the central pillars upon which the rest of the Torah rests.