There is also another factor that makes kedushah so critical for attaching ourselves to Hashem.
Ramchal among others explains that the “glue” that allows one to cling to Hashem is one’s “similarity,” so to speak, to Him.
In other words, if our conduct mirrors His conduct, if our actions are G-dly, we become in some way “similar,” as it were, to Hashem and thus cling to Him. This idea (for which there is a Latin phrase, “Imitatio Dei”) is mentioned in the Torah and Chazal in many ways, but perhaps is most explicit in the pasuk we have quoted: וְהִתְקַדִּשְׁתֶּם וִהְיִיתֶם קְדשִׁים כּיִ קָדוֹשׁ אָניִ , You are to sanctify yourselves and you shall be holy, for I am holy.
In this pasuk, Hashem tells Klal Yisrael: Become like Me and thereby attach yourselves to Me - by adopting My most defining middah, My kedushah.
In the words of the Ramban: “I want you to be holy so that you should be suited for Me, to cling to Me, for I am Holy.”
There are times that we feel connected to Hashem, whether after a meaningful tefillah, at Kabbalas Shabbos, or after a satisfying seder of learning. That connection is an infinitesimal sample, a distant echo of the experience of connection to Hashem that will be fully realized in Olam Haba.
It is a mei’ein Olam Haba. And that connection is predicated on one being kadosh.
Okay. Let’s regroup.
We have seen that the ultimate good is clinging to Hashem. Our neshamah’s realization of this pleasure drives us to have a connection to Hashem. We have seen also that since Hashem refers to Himself as Kadosh we can make ourselves similar to Him only by we, ourselves, emulating the middah of kedushah.
All this begs the question ... and what exactly is
kedushah?