Kedusha permeates many aspects of Avodas Hashem. There are four aspects of kedusha which, although different from one another, have unifying themes in common. There is kedushas makom, the sanctity of a geographic location such as the Beis Hamikdash and Eretz Yisrael; kedushas zman, the endowing of time with holiness, which includes Shabbos and yom tov; the words of Torah are holy and therefore sifrei Torah, tefillin and mezuzos are treated as sacred objects; and performance of mitzvos are an expression of kedusha that is incorporated into the text that is recited prior to mitzvah observance, "אשר קידשנו במצותיו".
For one to create a halachic status, it is often necessary that the particular area of halacha be relevant to the one attempting to do so. For example, one who is not obligated or does not wear tefillin is disqualified from writing the parshiyos for tefillin. Similarly, a non-Jew cannot be a shochet or a mohel because these mitzvos are not relevant to them. Following this model, only one who is endowed with kedusha could impart kedusha to other entities. Parshas Kedoshim begins with the identification of two sources of kedusha. The ultimate source of all kedusha is Hashem, Who is described as "כי קדוש אני ה׳ אלוקיכם". The Jewish people are commanded to emulate the characteristic of kedushas Hashem and are instructed to attain the level of "קדושים תהיו". Only Hakadosh Baruch Hu and His holy nation can, in turn, endow kedusha on others. Within the four dimensions of kedusha, Hashem and Klal Yisrael endow this sanctity.
There are two parts of kedushas makom, the kedusha of the Beis Hamikdash and of Eretz Yisrael. Halachically, these kedushas are each endowed differently. The Rambam explains this distinction between them as emanating from different sources. Hashem's Presence sanctifies the Beis Hamikdash, whereas Eretz Yisrael receives its holiness from the conquest and settlement of the land by the Jewish People. It is this distinction that results in a difference whether the kedusha can ever be removed. Concerning Eretz Yisrael, the laws that relate to agriculture depend on the status the Jewish People have in the land. At times the mitzvos of teruma, ma'aser and shemita may not be applicable d'oraysa if the vehicle that creates kedushas Eretz Yisrael, which is Klal Yisrael, is not present. Kedushas Beis Hamikdash, which results from Hashem, can never be suspended. The Rambam observes that "שכינה אינה בטלה" - the Divine Presence that sanctified the BeisHamikdash can never be removed.
Similarly, in the realm of kedushas zman there is a fundamental difference between Shabbos and yom tov. Hashem sanctifies Shabbos and therefore Shabbos existed before the birth of the Jewish People. Yom tov cannot exist without Klal Yisrael as it is the Jewish People that sanctifies Rosh Chodesh, thereby bringing about kedushas yom tov. Chazal highlight this difference in how they formulated the text of the tefillah and kiddush. On Shabbos we refer to Hashem as the One who is "מקדש שבת", and only on yom tov do we refer to Klal Yisrael as the prerequisite to kedushas yom tov by saying "מקדש ישראל והזמנים".
Within the world of Torah knowledge there are two aspects of kedusha. The תורה שבכתב and the parts of the תורה שבעל פה that were transmitted directly to Moshe on Har Sinai which were endowed with kedushas haTorah by Hashem. The Torah was given to Klal Yisrael to analyze and interpret properly. The portion of תורה שבעל פה that emanates from Chazal using the rules transmitted to משה רבינו as to how to correctly understand תורה attains its kedushas haTorah from kedushas Klal Yisrael. In the realm of mitzvah observance there are mitzvos from the Torah itself and others that were instituted by Chazal. We recite the identical beracha, "אשר קידשנו במצותיו", when we perform mitzvos such as matzo and shofar that were given directly by Hashem and when we light Chanuka candles and read the Megillah which were instituted by Chazal.
Kedusha bestowed by Hashem and by Klal Yisrael are related to one another. In the realm of kedushas makom this is apparent in the way Eretz Yisrael is sanctified. The method of conquest is accompanied by representation of the Beis Hamikdash. The special Kohen Gadol that goes out to accompany those sanctifying the land and the Aron that joins the battle highlight that the kedusha of Eretz Yisrael is an outgrowth of kedushas Hamikdash. Similarly, the yomim tovim are dependent upon Shabbos, as Shabbos is described as the "תחילה למקראי קדש - the first of the holy days.” Concerning Torah and mitzvos, halachos instituted by Chazal are modeled after direct word of Hashem - "כל דתקון רבנן כעין דאורייתא תיקון". The halachic guidelines that govern מצוות דרבנן are parallel to מצוות דאורייתא. The goal of דינים דרבנן is to preserve and enhance our observance of דינים דאורייתא.
Our privilege to endow place and time with sanctity and to incorporate דינים דרבנן into תורה ומצוות is contingent on our knowledge as to the source of our kedusha. "קדושים תהיו כי קדוש אני ה׳ אלוקיכם" - by imitating Hashem and living up to the standards of kedusha incumbent upon us, we are granted the opportunity to partner with Hashem in bringing kedusha to the world.
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