This blog is one big protest against superficiality so it is absolutely incumbent upon us to understand how our sanctity depends on the sanctity of Shabbos. We will not accept this passively and say "verrrry nice, we holy because Shabbos holy" and move on. What does this mean??
The psukim say that Hashem forged a covenant כרת ברית with Avraham [Nechemia 9/8, Lech Lecha 15/18]. Interestingly enough, we don't find the language of כרת ברית with respect to Bnei Noach. The depth is that כריתת ברית involves the exclusion of all others from the covenant that is forged. The covenant with Bnei Noach included all of mankind and excluded nobody so the term כריתת ברית wasn't appropriate. Hashem forged a covenant excluding all others with Avraham and his progeny alone.
One might think that the covenant with Avraham is built and predicated upon the general covenant with all of mankind. To disabuse [what a horrible word!] one from this notion the luchos habris were given to Avraham's children and they said that we must keep Shabbos which is in direct contrast to the covenant made with Noach where it says יום ולילה לא ישבותו - we are never allowed to stop working seven days a week. Shabbos thereby completely excludes us from the original bris with Noach.
Now we can understand how our sanctity is contingent upon Shabbos. Shabbos is what separates us from the nations of the world and proves that we have our own special covenant with Hashem that he forged [כרת] with us.
מקדש השבת וישראל והזמנים - Shabbos and Yisrael are really one. הא בהא תליא.
נפלא
Maran HaRav Hutner Shavuos תשל"ב. From the sefer Reshimos Lev.