Similar concepts also apply regarding the refinement of the non-Jewish nationsוְעַל דֶּרֶךְ זֶה הוּא גַּם בְּהָעִנְיָן דְּבֵרוּר הַגּוֹיִם כו'
(as alluded to in the verse “Praise G‑d, all you nations…”),(הַלְלוּ אֶת ה' כָּל גּוֹיִם גו')
for which potential is granted to the Jewish people on the holiday of Sukkos, as stated above in sec. 6.שֶׁבְּחַג הַסֻּכּוֹת,
This infusion of power comes as a result of the revelation of the dimension of yechidah on Rosh HaShanah and Yom Kippur.שֶׁזֶּה בָּא לְאַחֲרֵי הַגִּלּוּי דִּבְחִינַת יְחִידָה.
At this point, the maamar begins to correlate the concepts mentioned previously and address itself to the questions posed at the outset of the maamar.
To explain the matter: As a whole, the Divine service carried out during the Ten Days of Teshuvah emanates from the depths of the heart,וְהָעִנְיָן הוּא, דִּכְלָלוּת הָעֲבוֹדָה דַּעֲשֶׂרֶת יְמֵי תְּשׁוּבָה הִיא מֵעוֹמֶק הַלֵּב,
in the spirit of the verse,1 “I called You from the depths.”מִמַּעֲמַקִּים קְרָאתִיךָ.
The verse speaks of “depths,” in the plural, implying that there areוְאוֹמֵר מִמַּעֲמַקִּים לְשׁוֹן רַבִּים,
two distinct levels of depth, referring to those dimensions of the soul known as chayah and yechidah,2 the transcendent and essential dimensions of the soul, respectively.שְׁנֵי עֹמָקִים, חַיָּ' וִיחִידָה.
In particular, this applies on Rosh HaShanah (the beginning of the Ten Days of Teshuvah);וּבִפְרָט בְּרֹאשׁ הַשָּׁנָה (הַתְחָלַת עֲשֶׂרֶת יְמֵי תְּשׁוּבָה),
how much more so does it apply on Yom Kippur.וּמִכָּל שֶׁכֵּן בְּיוֹם הַכִּפֻּרִים
For among the Ten Days of Teshuvah themselves, Yom Kippur is “the time of repentance…, the final culmination of forgiveness and pardon being granted.”3שֶׁבַּעֲשֶׂרֶת יְמֵי תְּשׁוּבָה עַצְמָם הוּא זְמַן תְּשׁוּבָה כו' קֵץ מְחִילָה וּסְלִיחָה,
At this time, [a Jew’s] Divine service is concentrated in a dimension of singular oneness (yechidah)4 in all the three dimensions of space, time, and soul.5שֶׁהָעֲבוֹדָה אָז הִיא בִּבְחִינַת אַחַת (יְחִידָה) בְּכָל ג' הָעִנְיָנִים דְּעוֹלָם שָׁנָה נֶפֶשׁ.
Sefer HaYetzirah explains that all existence is dependent on three dimensions: olam, space (literally, “world”); shanah, time (literally, “year”); and nefesh, “soul.” During the Ten Days of Teshuvah, a Jew’s Divine service focuses on revealing the essential G‑dly core of the soul, the essence that is bonded with His Essence. When the Beis HaMikdash was standing, this spiritual service would culminate each year with the entry of the Kohen Gadol (the yechidah of nefesh) into the Holy of Holies (the yechidah of olam) on Yom Kippur (the yechidah of shanah).
The revelation of the dimension of singular oneness (which is elicited during all the Ten Days of Teshuvah, in particular on Rosh HaShanah and Yom Kippur) occurs on the festival of Sukkos.וְהַגִּלּוּי דִּבְחִינַת אַחַת (שֶׁנִּמְשְׁכָה בַּעֲשֶׂרֶת יְמֵי תְּשׁוּבָה וּבִפְרָט בְּרֹאשׁ הַשָּׁנָה וְיוֹם הַכִּפֻּרִים) הוּא בְּחַג הַסֻּכּוֹת
[As reflected in the well-known interpretation6 of the phrase7 “at the new moon, the appointed time of our festival.” Bakeseh, translated here as “at the new moon,”8 literally means “when it is concealed.” The phrase implies[כַּיָּדוּעַ בְּפֵרוּשׁ הַכָּתוּב בַּכֶּסֶה לְיוֹם חַגֵּנוּ,
that all matters are concealed and hidden (bake­seh) during the Ten Days of Teshuvah, and that theyשֶׁכָּל הָעִנְיָנִים שֶׁבַּעֲשֶׂרֶת יְמֵי תְּשׁוּבָה הֵם בְּכִסּוּי וְהֶעְלֵם (בַּכֶּסֶה),
are revealed during the festival of Sukkos.מִתְגַּלִּים הֵם בְּחַג הַסֻּכּוֹת.
This implies that during the Ten Days of Teshuvah, a Jew’s Divine service focuses on his G‑dly core, a dimension beyond revelation, and on Sukkos, the positive energies that were generated are now subsequently evoked and unfold into expression.
Accordingly, the Divine service of the Ten Days of Teshuvah is associated with weeping, which stems from an inward focus.וְזֶהוּ שֶׁהָעֲבוֹדָה דַעֲשֶׂרֶת יְמֵי תְּשׁוּבָה קְשׁוּרָה עִם בְּכִיָּ',
The emphasis on this mode of service is so great that the Arizal states that:9 “[When] one does not weep during the Ten Days of Teshuvah,10 his soul is imperfect.”וְעַד שֶׁמִּי שֶׁאֵינוֹ בוֹכֶה בַּעֲשֶׂרֶת יְמֵי תְּשׁוּבָה אֵין נִשְׁמָתוֹ שְׁלֵמָה,
This does not apply regarding Sukkos, “the season of our rejoicing,”מַה שֶּׁאֵין כֵּן סֻכּוֹת הוּא זְמַן שִׂמְחָתֵנוּ,
for joy is experienced specifically when its cause is in a revealed state.11כִּי שִׂמְחָה הִיא דַוְקָא מִדָּבָר שֶׁבְּגִלּוּי,
When is a person happy? When he actually feels the influence that triggers his joy. If that influence is concealed from him, existing merely in a latent state, he will not experience joy.
Moreover, joy itself leads to even further revelation of the factor that which caused the joy,וְעַל יְדֵי הַשִּׂמְחָה נִתּוֹסֵף עוֹד יוֹתֵר בְּהַגִּלּוּי,
for the natural tendency of joy is to bring inner, hidden potentials into a revealed state,12דְּטֶבַע הַשִּׂמְחָה הִיא לְהוֹצִיא מִן הַהֶעְלֵם אֶל הַגִּלּוּי,
When a person is happy, he displays his emotions freely. Moreover, all of his positive potentials are energized and express themselves with greater ease.
to the extent that it breaks through all constraints.]13וְעַד שֶׁהִיא פּוֹרֶצֶת כָּל גְּדָרִים].
There are two levels to the revelation of this dimension of singular oneness on the holiday of Sukkos, both of which are dependent on the actions of the Jewish people:וּבְהַגִּלּוּי דִּבְחִינַת אַחַת בְּחַג הַסֻּכּוֹת שְׁתֵּי דַרְגּוֹת.
The beginning of the revelation is brought about by dwelling in the sukkah.דִּתְחִלַּת הַגִּלּוּי הוּא עַל יְדֵי יְשִׁיבָה בַּסֻּכָּה,
Chronologically, the obligation to dwell in a sukkah begins at the commencement of the holiday, being that the observance of this mitzvah is what initiates the spiritual revelations associated with the holiday.
It highlights the aspect of singular oneness, as reflected by our Sages’ statement:14בְּחִינַת אַחַת,
“All Israel is worthy of dwelling in one sukkah.”15כָּל יִשְׂרָאֵל רְאוּיִים לֵישֵׁב בְּסֻכָּה אַחַת.
This revelation is manifest in an encompassing (makkif) manner.וְגִלּוּי זֶה הוּא בִּבְחִינַת מַקִּיף.
The term makkif, “encompassing,” implies a revelation that is transcendent in nature and which is therefore described as being above a person’s individual identity.
Next in the sequence, through the mitzvah of taking the four species this revelation is internalized, as explained in various sources.16 The four species are held against a person’s heart when fulfilling the mitzvah, i.e., he “takes to heart” the spiritual influences that they arouse and makes them part of himself.וְעַל יְדֵי מִצְוַת נְטִילַת ד' מִינִים נִמְשָׁךְ הַגִּלּוּי בִּפְנִימִיּוּת, וְכַמְּבוֹאָר בְּכַמָּה מְקוֹמוֹת.
These concepts are to be connected with the explanations above (sec. 2), which state that there are two distinct dimensions of singular oneness reflected by the mitzvos of Sukkos:וְיֵשׁ לְקַשֵּׁר זֶה עִם הַמְבוֹאָר לְעֵיל (סְעִיף ב)
The unity reflected by the mitzvah of dwelling in the sukkah is an essential unity, which does not recognize for any divisions among different levels; rather, it highlights the fundamental commonality shared equally by all Jews.שֶׁהָאַחְדּוּת דְּסֻכָּה הִיא אַחְדּוּת בְּעֶצֶם שֶׁמִּלְּכַתְּחִלָּה אֵין בָּהּ הִתְחַלְּקוּת פְּרָטִים
In contrast, the unity reflected by the mitzvah of taking the four species involvesמַה שֶּׁאֵין כֵּן הָאַחְדּוּת שֶׁבְּמִצְוַת נְטִילַת ד' מִינִים הִיא
the recognition that even though distinct entities do exist, they nevertheless merge and join togther in unity.דַּהֲגַם שֶׁיֶּשְׁנָם פְּרָטִים מְחֻלָּקִים מִכָּל מָקוֹם הֵם בְּאַחְדּוּת,
The reason for these differing emphases is that the process of internalization involves relating to different distinct qualities that exists within one’s own self and within others.17כִּי פְּנִימִי הוּא בִּבְחִינַת הִתְחַלְּקוּת,
Accordingly, the unity of the sukkah, which does not recognize distinction, is manifest in an encompassing manner.וְלָכֵן, הָאַחְדּוּת דְּסֻכָּה שֶׁאֵין בָּהּ הִתְחַלְּקוּת, הִיא בִּבְחִינַת מַקִּיף,
The sukkah relates to every Jew, no matter who he be, because it highlights the essential G‑dly core of our being, which is above our individual identities.
Through the unity reflected by the four species,וְעַל יְדֵי הָאַחְדּוּת בְּד' הַמִּינִים,
which parallel the four categories that comprise the Jewish people,שֶׁהֵם כְּנֶגֶד ד' סוּגִים שֶׁבְּיִשְׂרָאֵל,
and similarly, which parallel the four levels in the soul18 of every Jew,וְעַל דֶּרֶךְ זֶה כְּנֶגֶד ד' הַדַּרְגּוֹת שֶׁבְּכָל אֶחָד,
The soul’s attributes reflect (as does all existence) the Sefiros alluded to by the four letters of G‑d’s name י-ה-ו-ה: Chochmah, Binah, Z’eir Znpin (the emotive attributes), and Malchus, respectively.
this unity is elicited and internalized.הִיא נִמְשֶׁכֶת בִּפְנִימִיּוּת.

Summary

A Jew’s ability to refine the non-Jewish nations that is granted him on Sukkos is an outgrowth of the revelation of the dimension of yechidah in the Jews’ Divine service during the Ten Days of Teshuvah, particularly during Rosh HaShanah and Yom Kippur.
Through Divine service that emanates from the very depth of his being during those days, a Jew evokes G‑d’s essential singular oneness, which is then drawn into and revealed in an encompassing (makkif) manner through the mitzvah of dwelling in the sukkah and in turn internalized through the mitzvah of taking the four species. These mitzvos thus reflect two different dimensions of unity:
(a) the essential singular oneness reflected by the mitzvah of dwelling in the sukkah, which does not recognize any distinction between different levels;
(b) the oneness reflected by the mitzvah of taking the four species, which joins distinct entities in unity.