Shabbos empowers Yisrael's holiness

עוד במד' קדושים תהיו יכול כמוני ת"ל כי קדוש כו' קדושתי למעלה מקדושתכם.

Further, in the Midrash: "'You shall be holy' — could this mean like Me? The verse teaches, 'For I am holy...' — My holiness is above your holiness."

The Torah commands us to be kadosh (holy), but one might think we are meant to reach Hashem's own holiness. The Midrash clarifies that Hashem's holiness is on an utterly higher plane than ours.

הפי' דכתי' כי קדוש אני ה"א.

The explanation: as it is written, "For I, Hashem your God, am holy."

The Sefas Emes begins to unpack what this distinction between Hashem's holiness and ours really means.

פי' כמו שהקב"ה למעלה קדוש ונבדל מכל השרים ומנהיגים.

The meaning: just as the Holy One, blessed is He, is above — holy and set apart from all the heavenly princes and rulers.

Hashem's kedushah means He is entirely separate and transcendent, above every angelic power that governs the world.

כמו כן בנ"י עם ה' צריכין להיות למטה קדוש ונבדל מכל התחתונים.

So too Bnei Yisrael, the people of Hashem, must be holy and set apart below, from all the lower beings.

Our task of kedushah parallels Hashem's: down here in this world, Bnei Yisrael are to remain separate and distinct from the surrounding nations and their ways.

יכול כמוני שנוכל להיות כ"כ קדוש ונבדל מן העמים כמו שהקב"ה קדוש ונבדל למעלה ת"ל כו' שאין כח בנו להיות נבדל לגמרי מהם.

"Could this mean like Me" — that we could be so holy and set apart from the nations as the Holy One is holy and set apart above? The verse teaches that we do not have the power to be completely separated from them.

On our own, Bnei Yisrael cannot achieve the total, absolute separation from the nations that mirrors Hashem's transcendence — our natural strength is not enough for a complete havdalah.

אך בש"ק דכתי' ביני ובין בנ"י אות היא כח השבת מסייע לנו להיות נבדל מהם.

But on Shabbos Kodesh, of which it is written, "Between Me and Bnei Yisrael it is a sign forever," the power of Shabbos helps us to be separated from them.

Shabbos, the special "sign" between Hashem and His people, supplies a power beyond our own that enables us to attain a separation from the nations we could not reach unaided.

וכן איתא האל הקדוש שאין כמוהו המנחיל מנוחה כו' שבש"ק דכתי' אני ה' מקדישכם יכולין להיבדל לגמרי מן העמים כמ"ש המבדיל בין קודש לחול בין ישראל לעמים:

And so it is said: "the holy God, to whom none compares, who grants rest..." — for on Shabbos Kodesh, of which it is written, "I am Hashem who sanctifies you," we are able to be completely separated from the nations, as we say, "who separates between the holy and the profane, between Yisrael and the nations."

On Shabbos, when Hashem Himself sanctifies us, the complete separation that is otherwise beyond our reach becomes possible — which is why the havdalah blessing pairs the divide between holy and profane with the divide between Yisrael and the nations.

Summary: Bnei Yisrael are commanded to be holy and separate just as Hashem is, yet on our own we cannot attain a complete separation from the nations. The power of Shabbos, the sign between Hashem and His people on which He Himself sanctifies us, lifts us to that otherwise unreachable level of total kedushah and havdalah.