K'doshim: What does it mean to be holy?

Baruch atah Adonai
Eloheinu Melech ha-olam
asher kid'shanu b'mitzvotav
v'tzivanu la'asok b'divrei Torah.

Rabbi Hiyya, who lived in Israel during the third century, stresses that Moses was told to present the commandment, "You shall be holy, for I, the Lord your God, am holy," to "the whole Israelite community." The commandment was given not to a few pious priests or individuals but rather to the entire community. Achieving a state of holiness, therefore, is not something done by one person or a small group of persons but rather by the whole people.
~Fields, p. 132

The Sifra, a fourth-century commentary on Leviticus, interprets the words "kedoshim tiheyu" ("you shall be holy") as perushim tiheyu" ("you shall be separate"). Some scholars say this is a reference to the Pharisees, who were known by the Hebrew name Perushim and who taught that Jews achieved "holiness," or a special status of honor by God, if they carefully observed all the commandments.
~Fields, p. 132

Does this mean that Jews are to withdraw from the societies in which they live or from contact with people of other religions and national origins? Modern philosopher Martin Buber says no. He writes: "Israel must, in imitating God by being a holy nation, similarly not withdraw from the world of the nations but rather radiate a positive influence on them through every aspect of Jewish living." For Buber being kadosh, or "different, unique," does not mean retreating from contact with other religious and national groups. Instead, it is a special goal and responsibility. It means the Jewish people must achieve an ethical and spiritual excellence that can enrich and "influence" all other peoples. (Darko shel Mikra, p. 90)
~Fields, p. 132

Rabbi Chaim Sofer comments that "to be holy"... means "not merely in the privacy of your home and ashamed of your faith in public. Be not, as the assimilationists put it, 'A Jew at home and a man outside.' Be holy 'in the community,' in public, out in the open, in society. Among your own people or in the midst of strangers, wherever you may find yourself, never be ashamed of your character and sanctity as a Jew."
~Divre Sha'are Chaim, as quoted in Fields, p. 133

But what does it mean to be holy? The next few verses offer rules for Israelite life, but are they intended to promote holiness, or was the opening statement of the Torah portion a charge unrelated to the statements that follow? Can honoring our parents, observing the Sabbath, renouncing idolatry, or leaving the produce on the edges of our fields for the poor make us holy? Is abstaining from theft, deceitful practices, or withholding our workers’ wages until the end of the week enough to make us holy?
Commentators have struggled with this verse for centuries. Rashi, noting the lists of prohibited sexual relationships in Leviticus 18 and 20, thinks the opening verses of Leviticus 19 are a reminder to avoid sexual impropriety. Nachmanides argues that the Torah is aware that we could observe the letter of the law while still over-indulging in permitted activities, or in his words: “One could be a scoundrel with the full permission of the Torah” (Nachmanides on Lev. 19:2). For this reason, he says, we are given an overarching directive to be holy – that is, to be moderate even in permissible activities.
~https://reformjudaism.org/learning/torah-study/torah-commentary/what-makes-us-holy

Each of us has the capacity for holiness. But no one can achieve a k’dushah that mirrors the holiness of God. When we see ourselves as members of the people Israel, of a people called to be holy, we let go of the unbearable burden of attaining perfection as individuals. Each of us can choose the mitzvot that allow us to express our unique Jewish self, knowing that through our individual Jewish lives, we are contributing to the Jewish whole. Am Yisrael is holy not because each of us upholds at all times the highest expression of Judaism, but because each of us brings to the community a spark of holiness.
~https://reformjudaism.org/learning/torah-study/torah-commentary/what-makes-us-holy

הַרֵינִי מְקַבֵּל עָלַי אֶת מִצְוָת הַבּוֹרֵא וְאָהַבְתָּ לְרֵעֲךָ כָּמוֹךָ
Hareini m'kabel alai et mitzvat haborei (2x)
V'ahavta (V'ahavta) l'reiacha (l'reiacha) kamocha (kamocha) (2x)
Zeh k'lal gadol...
I take upon myself the instruction of the creator to love your neighbor as yourself.
~Alter Rebbe of Lubavitch / Music by Jacob Spike Kraus

One of the earliest explanations of the Torah's commandment comes in the form of a story told about Rabbi Hillel, a popular teacher of the first century B.C.E. Once a non-Jew challeneged him with the promise: "I will convert to Judaism if you can teach me the whole Torah while I stand on one foot." Rabbi Hillel's response was immediate. "What is hateful to you do not do to your neighbor. That is the whole Torah. The rest is commentary. Now go and learn it."
~Shabbat 31a, as quoted in Fields, p. 134

"You should remember that you and your neighbor were created in the likeness of God." In other words, we are to treat others with respect and love, not because we are commanded to do so, not because we understand their feelings, tastes, or reactions to be like our own. We are to respect the rights, dignity, and feelings of others because, like us, they were created in God's likeness.
~Genesis Rabbah 24, as quoted in Fields, p. 135

As to the character of our love, Maimonides is quite specific. Loving your neighbor as you love yourself means visiting the sick, comforting mourners, joining in a funeral procession celebrating the marriage ceremony with bride and groom, offering hospitality, caring for the dead, or delivering a eulogy. Concluding his list of examples, Maimonides writes: "All the things that you would want others to do for you—do for your brothers and sisters."
~Mishneh Torah, Hilchot Evel 14:1, as quoted in Fields, p. 135

The idea that love for oneself and love for others are mutually connected forms the basis of modern psychologist Erich Fromm's classic work The Art of Loving. Stressing the importance of "self-love," Fromm writes, "The idea expressed in the biblical 'Love your neighbor as yourself!' implies that respect for one's own integrity and uniqueness, love for and understanding of ones's own self, cannot be separated from respect and love and understanding for another individual. The love for my own self is inseparably connected with the love for any other being."
~Fields, p. 136-137

If you can't love yourself, how in the hell you gonna love somebody else? Can I get an Amen?
~Rupaul Charles, at the end of every episode of Rupaul's Drag Race

At v'kara zeh, bow to the left; at el zeh, bow to the right. We rise on our tows at each mention of kadosh. Some people do so once also at Barukh k'vod and again at Yimloch (Ben Ish Chai, T'rumah 4-6), but Halakhah forbids any attempt to jump into the air (Rema 122:2, Mishnah B'rurah 7). It is best to retain a full, reverential posture until the reader has completed the blessing...
Landes, My People's Prayer Book, Vol. 2, The Amidah, p. 91

We should also contemplate Isa. 6:3 from which the prayer is taken, in its Aramaic translation. From here we learn that the first "holy" refers to God's holiness in the heavens above, the residence of the divine. The second "holy" is God's holiness on earth, the handiwork of divine creativity. And the third "holy" evokes God's holiness in time, for ever and ever. This then is the meaning of the next phrase in the Isaiah verse, "The whole world id filled with the radiance of the divine Glory!" God's holiness is heavenly, earthly, and temporal.
The Isaiah passge goes on to describe how the prophet saw a seraf (a fiery angel) "fly" with a pair of wings, "And with two the seraf would fly." Thus, through our own sacred choreography we literally "fly" just like the angels themselves! And this is the origin, suggests Rabbi Levi Yitchak of Berditchev, of "fluttering" on one's feet, standing on our tiptoes with each mention of kadosh, "holy."
Kushner & Polen, My People's Prayer Book, Vol. 2, Amidah, p. 89