Chazal teach us that the number eight indicates completion and perfection but also hints at new beginnings. Rav Shamshon Refa’el Hirsch uses an analogy to an octave of musical notes to explain this: The eighth and final note of an octave is also the first note of the next, higher octave.
Many Mefarshim explain the Pasuk that opens our Parashah, “VaYehi BaYom HaShemini," “And it was on the eighth day” (VaYikra 9:1), not to refer to the eighth day of Nisan but rather the first of the month, ending a week of preparation for the Mishkan’s inauguration. Furthermore, the Gemara (Megilah 10b) adds that Hashem’s joy at that time was equal to His joy at the time of Creation, seemingly because they were both the same joy, that of new life and new beginnings. In fact, Rashi notes that the “Yom HaShemini” actually had ten beginnings, among which were: The beginning of the year; the beginning of the Kohanim’s Avodah in the Mishkan; and the beginning of the Shechinah’s residing in the Mishkan.
The Pasuk later states, "VaYomer Moshe Zeh HaDavar Asher Tzivah Hashem Ta’asu VeYeira Aleichem Kevod Hashem," “And Moshe said, ‘This is what Hashem has commanded that you do, that the Glory of Hashem may appear to you’” (VaYikra 9:6). Conspicuously absent from this Pasuk is any indication of what “this” is. Both the Torat Kohanim and Targum Yonatan suggest “Zeh” means elevating one’s Yeitzer HaRa to use in the service of Hashem.
There are several lessons that can be gleaned from both this idea and the idea that the eighth day represents a new beginning. If we wish to live a meaningful life we must live each day with the enthusiasm and zeal of the first day. Every day we must take new steps, however small, to improve our Torah learning and Midot. This is especially applicable now during Sefirat HaOmer, as the rabbis teach that each day we should focus on a different facet of our character as we effectuate a transformation from our slave mentality from before Pesach to witnesses to Hashem’s Revelation at Har Sinai on Shavuot. Indeed, Shavuot comes at the outset of the “Eighth” week of the Omer, a new beginning after leaving Mitzrayim.
This message of zeal and constant improvement is suggested elsewhere in the Parashah. Shemini is the midpoint of the Torah in terms of letters – the words "Darosh Darash," “Inquire diligently” (VaYikra 10:16), are the exact center – on which the Rabbis expound that, "Just as you have strived to acquire Torah knowledge until now, so may you go forward from this point, and continue to strive to acquire more Torah knowledge."
This lesson of the number eight thus provides a first step in our life long mission to strive for a spiritually complete and meaningful life: Keep building, treating every end as a new beginning, to reach new spiritual heights.