Acharei Mot/ Kedoshim 5786
Are there four worlds of holiness?

(ב) דַּבֵּ֞ר אֶל־כׇּל־עֲדַ֧ת בְּנֵי־יִשְׂרָאֵ֛ל וְאָמַרְתָּ֥ אֲלֵהֶ֖ם קְדֹשִׁ֣ים תִּהְי֑וּ כִּ֣י קָד֔וֹשׁ אֲנִ֖י יהוה אֱלֹהֵיכֶֽם׃ (ג) אִ֣ישׁ אִמּ֤וֹ וְאָבִיו֙ תִּירָ֔אוּ וְאֶת־שַׁבְּתֹתַ֖י תִּשְׁמֹ֑רוּ אֲנִ֖י יהוה אֱלֹהֵיכֶֽם׃

(2) Speak to the whole Israelite community and say to them:
You shall be holy, for I, the ETERNAL your God, am holy. (3) You shall each revere your mother and your father, and keep My sabbaths: I the ETERNAL am your God.

Why are the commandments in 19:3 the ones directly following the commandment to aspire to holiness? Perhaps because these are the ones to span the generations and touch eternity! This is the first world of Holiness, the foundation of all.

קדשים תהיו. הֱווּ פְרוּשִׁים מִן הָעֲרָיוֹת וּמִן הָעֲבֵרָה, שֶׁכָּל מָקוֹם שֶׁאַתָּה מוֹצֵא גֶדֶר עֶרְוָה אַתָּה מוֹצֵא קְדֻשָּׁה, אִשָּׁה זֹנָה וַחֲלָלָה וְגוֹ' אֲנִי יהוה מקדשכם (ויקרא כ"א), וְלֹא יְחַלֵּל זַרְעוֹ, אֲנִי יהוה מְקַדְּשׁוֹ (שם), קְדֹשִׁים יִהְיוּ, אִשָּׁה זֹנָה וַחֲלָלָה (שם):

קדשים תהיו YOU SHALL BE HOLY — This means, keep aloof from the forbidden sexual relations just mentioned and from sinful thoughts. Wherever you find in the Torah a command to fence yourself in against such relations you also find mention of “holiness". Examples are: (Leviticus 21:7) “[They shall not take] a wife that is a harlot etc.", and in the next verse "for I, the Lord, who sanctify you"; (Leviticus 21:15) “Neither shall he profane his seed for I the Lord do sanctify him"; (Leviticus 21:6) "They shall be holy… followed by (v. 7) "[they shall not take] a wife that is a harlot or a profane" (cf. Vayikra Rabbah 24:4-6).

Rashi speaks of holiness on the level of negative commandments. This is another level of Holiness. During this era of "me too" where incest is taboo to speak of and Epstein and his cronies did not believe in boundaries, it is important to keep trust within communities and families, not to allow power to take advantage. Sex only with consenting adults

(יח) לֹא־תִהְיֶ֥ה קְדֵשָׁ֖ה מִבְּנ֣וֹת יִשְׂרָאֵ֑ל וְלֹֽא־יִהְיֶ֥ה קָדֵ֖שׁ מִבְּנֵ֥י יִשְׂרָאֵֽל׃

(18) No Israelite woman shall be a kadeshah, nor shall any Israelite man be a kadesh.

קְדֵשָׁה (n-f) heb
female temple prostitute, harlot
Source: מקור: Open Scriptures on GitHub
Creator: יוצר: Based on the work of Larry Pierce at the Online Bible
† I. קָדֵשׁ n.m. temple-prostitute, male Source: מקור: BDB Dictionary
Creator: יוצר: F. Brown, S. Driver & C. Briggs
The prohibition in Deuteronomy of ritualized sex to appease the gods is perhaps the second level of meaning, a path of holiness to be spurned. The fact that it is mentioned as a prohibition implies that it was likely being performed in biblical times. For the non-incest prohibitions in Leviticus 18, it may be the rationale.

(ב)ואהבת לרעך כמוך. אָמַר רַבִּי עֲקִיבָא זֶה כְּלָל גָּדוֹל בַּתּוֹרָה (ספרא):

(2) ואהבת לרעך כמוך THOU SHALT LOVE THY FELLOW MAN AS THYSELF —Rabbi Akiba said: “This is a fundamental principle of the Torah” (Sifra, Kedoshim, Chapter 4 12; Talmud Yerushalmi Nedarim 9:3).

We make our lives holy when we dedicate ourselves to one another, when we unite humans together, despite all the obstacles between us and the yetzer haRa - the selfish, "getting what you want by force" way of creating or getting things. This perhaps is the third level of aspiring to be holy, - v'ahavta l're'acha kamocha, love your near one as yourself in feeling and in doing mitzvot to support them

(א)הוא אשר דבר וגו'. הֵיכָן דִּבֵּר? וְנֹעַדְתִּי שָׁמָּה לִבְנֵי יִשְֹרָאֵל וְנִקְדַּשׁ בִּכְבֹדִי (שמות כ"ט), אַל תִּקְרֵי בִּכְבֹדִי אֶלָּא בִּמְכֻבָּדַי; אָמַר לוֹ מֹשֶׁה לְאַהֲרֹן, אַהֲרֹן אָחִי, יוֹדֵעַ הָיִיתִי שֶׁיִּתְקַדֵּשׁ הַבַּיִת בִּמְיֻדָּעָיו שֶׁל מָקוֹם, וְהָיִיתִי סָבוּר אוֹ בִי אוֹ בְךָ, עַכְשָׁיו רוֹאֶה אֲנִי שֶׁהֵם גְּדוֹלִים מִמֶּנִּי וּמִמְּךָ (ספרא):

(1) ‎‎ '‏וגו‎‎‎ 'הוא אשר דבר ה‎ THIS IS WHAT THE LORD SPOKE, etc. — Where had He spoken this? In the statement (Exodus 29:43), “And there I will be met by the children of Israel and it (the Tabernacle) shall be sanctified by My glory (בכבודי).” Read not here בִכְבוֹדִי, “by My Glory” but בִּמְכֻבָּדַי, “through My honoured ones” (Zevachim 115b). Moses here said to Aaron: “My brother, Aaron! I knew that this House was to be sanctified by those who are beloved of the Omnipresent God and I thought it would be either through me or through thee; now I see that these (thy sons who have died) are greater than me and than thee!” (Leviticus Rabbah 12 2).

(ג) וְקָרָ֨א זֶ֤ה אֶל־זֶה֙ וְאָמַ֔ר קָד֧וֹשׁ ׀ קָד֛וֹשׁ קָד֖וֹשׁ יהוה צְבָא֑וֹת מְלֹ֥א כׇל־הָאָ֖רֶץ כְּבוֹדֽוֹ׃

(3)And one would call to the other,“Holy, holy, holy! GOD of Hosts—
Whose presence fills all the earth!”

G8d's presence is not just transcendent, but immanent and able to be connected with. In Acharei Mot, Aarons sons Nadav and Avihu find the wrong path, perhaps, to a mystical union with G8d. This is why their offering is "aish zarah" strange fire. d central tenet of Judaism: u'vacharta b'chayim - choose life!

(י) וענין השוערים והשמות האלו, פירושן הוא, כי היו משביעים בכח שם קדוש אחד שהוא מן הספירה שבאותה מדרגה אל המלאך המושרש ונחצב משם והוא הממונה על שער הרקיע עצמו שהוא החומר שבמדרגה ההיא, אשר יש לו גם כן שם ידוע לאותו שער, ופותחו, ואז נכנסת מחשבת הנביא דרך שער ההוא מאור לאור עד אור הפנימי של הספירה שבאותה מדרגה, ואז מתפלל ומיחד היחוד הצריך לשם, וכך עולה ממדרגה למדרגה:

(10) The explanation of the matter of the gates and names, is that they would use the power of a holy name that relates to the Sefirah of that level, to bind by oath, the angel that is rooted to that level. That angel is appointed to guard the gate of that firmament itself, which is the substance (Chomer) of that level, and the gate also has a known name, which the angel would open. The thought of that prophet would then ascend by way of that gate from one light to the next light, until it reached the inner light of the Sefirah of that level itself. He would then pray and make the unification (Yichud) needed for that level, and in this manner, he would ascend from level to level.

Gates of Holiness: To attain you must be alone, so that your contemplation not be disturbed. In your mind, cultivate aloneness to the uttmost. Strip your body from your soul, as if you do not feel that you are clothed in matter at all--you are entirely soul. The more you strip yourself of material being, the more powerful your comprehension...supernal holiness does not abide with anyone attached by even a hair to the material realm. This is the secret reason that a band of prophets has timbrels flutes and other instruments --for in the sweetness of the melody, aloneness descends on them and they strip their souls... Strengthen yourself and pray this prayer with perfect intention.
"Master of all worlds, to you it is revealed and known that I am not engaged in this for my own glory, but rather for the glory of Your name, for the glory of the oneness of your being, so that I will know You, how to serve You and bless Your name. Enlighten my eyes lest I sleep the sleep of death. Create a pure heart within me"
...Sanctify your limbs and adorn them with Mitzvot making yourself into a throne for the Divine Presence, your body an ark for the Shechina! p 122-3 Essential Kabbalah by Danny Matt
This is the fourth level - the sod or mystery - the ultimate aim of aspiring for holiness is those flashes of inspiration and knowledge that all is one, it's all G8d. This is why kedoshim t'hyu is the same as v'ahavta l're-acha kamocha in being central pillars around which the rest of Torah and our lives can be arranged and given direction! I suggest that the "ani Adonai which follows some of these commands are, on this level meant to dissolve the barriers between Ani and Adonai
with an eye made quiet by the power
of harmony, and the deep power of joy
we see into the life of things (note the synesthesia of the "eye" quieted by "harmony" reminiscent of seeing Sinai's thunder!)~ from William Wordsworth's (fitting name for a poet!) Tinturn Abby, quoted in Rabbi Aviva Gottleib Zornberg's Hidden Order of Intimacy commentary on Leviticus