By Alexander Poltorak
לע”נ אבי מורי, אברהם שמשון ע”ה בן ראובן
Between the jubilation of Rosh HaShanah and the solemnity of Yom Kippur lie ten transformative days that hold the power to reshape our relationship with the divine. While commonly known as the Ten Days of Penitence (Aseret Yemei Teshuvah), Jewish mysticism reveals a deeper dimension to this period, referring to these days as nesira—literally “cutting” or “sawing.” This mystical concept offers profound insights into both the nature of spiritual transformation and the very structure of divine reality itself.
The Primordial Separation: Adam and Eve
To understand nesira, we must journey back to the very beginning, to the mysterious double narrative of human creation in Genesis. The Torah presents us with two seemingly contradictory accounts of how humanity came to be.
The first account speaks of a unified creation:
So G‑d created man in His own image, in the image of G-d He created him; male and female He created them… (Genesis 1:27)
The Midrash explains that this first human was a composite being—male and female united in a single form. Some sources describe them as joined side to side like conjoined twins,[1] while others envision them attached back to back.[2] In this primordial state, although physically connected, they could not truly see each other, could not relate, could not mate, and could not form a conscious bond.
The second narrative in Genesis provides the crucial next chapter:
So the Eternal G‑d caused a deep sleep to fall upon the man, and he slept; and He took one of his sides, and closed up the flesh in its place. And the Eternal G‑d built the side that He had taken from the man into a woman, and He brought her to the man. (Genesis 2:21-22)
This divine surgery—this original nesira—transformed unconscious attachment into a conscious relationship. Only after being separated could Adam and Eve face each other, recognize one another, fall in love, and choose to unite. The separation paradoxically enabled true union.
The Zohar’s Insight
The Zohar elevated this biblical narrative into a cosmic principle. Rabbi Shimon bar Yochai teaches:
When man was created, he was created with two faces, one on this side and one on that side. And the Holy One, blessed be He, sawed them apart and made him with a back here and a back there. As it is written, ‘He took one of his ribs’ (Genesis 2:21)—this you should read not as ‘his ribs’ [mitzalotav] but as ‘his side’ [misitrov]. (Zohar I, 34b)
This Zoharic passage introduces the Hebrew term that would become central to Kabbalistic thought: nesira, from the root meaning “to saw.” The image is striking—the Divine as cosmic surgeon, carefully separating what was once joined to enable a higher form of connection.
Lurianic Kabbalah: The Cosmic Drama
The 16th-century master Isaac Luria (the Ari) transformed this concept into an elaborate cosmic drama involving the divine Partzufim—archetypal personas that govern spiritual reality. In Lurianic cosmology, Zeir Anpin (the “Small Face”) represents the masculine divine principle, while Nukva (the “Female”) embodies the feminine aspect of divinity.
The Ari’s student, Rabbi Ḥayyim Vital, records his teacher’s deep insight:
Initially, when Nukva was created, she was attached to the back of Zeir Anpin, in a state of back-to-back, and her single point was at the level of his back, opposite the place of his heart… and then she was sawed away from there, and he built her up and rectified her as a complete Partzuf of ten sefirot. (Etz Chaim, Sha’ar 36, Ch. 2)
This technical description reveals Ari’s profound insight: the feminine divine begins as an undeveloped potential, a single point attached to the masculine divine. The nesira is not merely separation but the first step in a process of maturation and empowerment.
The Shofar as Cosmic Saw
Most remarkably, the Ari connected this mystical process to the very heart of Rosh HaShanah observance—the sounding of the shofar. Rabbi Vital explains:
The primary intention of the shofar is to perform the nesira upon Nukva of Zeir Anpin and to separate her from being attached to his back… The three blasts, Tekiah, Shevarim, Teruah, contain the power of the three letters of the word ‘neser’ (נסר), which means a “saw”… For through the power of the shofar blasts, the sawing is performed upon her, and she is separated from his back. (Sha’ar HaKavanot, Drushei Rosh HaShanah, Drush 1)
The shofar blast becomes more than a symbol—it is the mystical tool that initiates cosmic transformation. The very sounds that awaken us to repentance simultaneously perform surgery in the heavenly realms.
The Ten-Day Process
The Ari reveals that this nesira is not instantaneous but unfolds over the Ten Days of Repentance in a carefully orchestrated progression:
The matter of the nesira extends through these ten days… And this is the secret of the Ten Days of Repentance, for in them the nesira is completed. For on each and every day of them, one sefirah is sawed from the ten sefirot of the backside of Zeir Anpin, and one of the ten structures of her [Nukva’s] own is built from it… (Sha’ar HaKavanot, Drushei Rosh HaShanah, Drush 3)
Each day becomes a workshop of divine construction. Beginning with Keter on the first day of Rosh HaShanah and concluding with Malkhut on Yom Kippur, each of the ten divine emanations (sefirot) is carefully separated and reconstructed. By Yom Kippur, the Day of Atonement, this cosmic construction project reaches completion, enabling the ultimate face-to-face union between the divine masculine and feminine.
Chasidic Psychology: The Soul’s Nesira
The Chabad Rebbes brought this lofty mystical concept down to earth, applying it to the psychology of spiritual transformation. The Alter Rebbe, founder of Chabad Chasidism, writes:
And this is the matter of the nesira, which is the matter of teshuvah (repentance): to saw and to separate the evil from the good… Just as it was in the creation of the world that the Nukva was included in Zeir Anpin back-to-back, and afterward there was the nesira… so it is with a person, where the animal soul is intermingled and enclothed within the divine soul… and through teshuvah, one separates the evil. (Maamarei Admur HaZaken, 5565)
Here, the cosmic drama becomes intensely personal. Within each person, the divine soul and animal soul exist in a state of back-to-back entanglement—present to each other but unable to achieve conscious, harmonious relationship. The process of teshuvah (repentance) becomes the personal nesira, the careful separation of higher from lower impulses.
The Fifth Lubavitcher Rebbe, Rabbi Sholom Dovber Schneersohn, adds another dimension:
“Neser” [a saw] is an expression of cutting, as one cuts a thing in two. This is like when one wants to make a new vessel, one must take wood or stone, saw it, and remove the waste… So it is below in the service of man: the nesira is the submission and nullification, where one nullifies oneself in order to come to a new state of being. (Hemshech “Yom Tov Shel Rosh Hashanah,” 5666)
This perspective frames nesira as constructive destruction—the necessary clearing away of ego and negative patterns to create space for spiritual reconstruction.
Scientific Resonances: From Mysticism to Physics
Remarkably, this ancient mystical concept finds a parallel in modern physics.
The most direct parallel for the nesira is disengagement. I discussed this at length in “Yom Kippur – Disentangling the Entangled.”
When it comes to “face-to-face” or “back-to-back” types of relationships, it is more difficult to find parallels, because these expressions are themselves metaphors. However, a few analogies from physics come to mind.
Wave Interference: In wave physics, waves that meet “face to face” (in phase) create constructive interference, amplifying each other. Waves that are “back to back” (out of phase) create destructive interference, canceling each other out. The mystical goal of transitioning from back-to-back to face-to-face relationships mirrors the shift from destructive to constructive wave interaction.
Quantum Entanglement: In quantum mechanics, entangled particles maintain a “face-to-face” relationship—instantaneous correlation regardless of distance. When quantum systems decohere, they become “back-to-back”—disconnected, disordered, and acting independently. The spiritual work of the Ten Days aims to restore the coherence and our entanglement with the Divine.
Resonance: Physical systems in resonance transfer energy efficiently in a “face-to-face” relationship. Out-of-resonance systems remain energetically isolated despite proximity—a “back-to-back” state. The Ten Days of Repentance are fundamentally about achieving resonance with the Divine frequency.
These analogies are intended to aid understanding of these highly abstract concepts and should not be taken literally.
The Contemporary Message
The concept of nesira speaks powerfully to our contemporary moment. In our hyperconnected yet often spiritually disconnected age, many of us find ourselves in “back-to-back” relationships—physically or virtually present but not truly seeing each other. We may be staring at our phones while having dinner with our spouse. We may be attached to religious practices through habit or heritage, but lack the conscious, face-to-face encounter with the divine.
The Ten Days of Repentance offer an annual opportunity for spiritual nesira—the courageous work of cutting away what stands in the way of an authentic relationship. This might mean separating from negative patterns that entangle us unconsciously or sawing away cynicism to rediscover wonder and awe—we all know our vices and challenges.
Like any surgery, this process requires courage, precision, and faith. The mystical tradition assures us that what appears as separation is actually preparation for unprecedented intimacy.
The Ultimate Union
The goal of nesira is not permanent separation but eventual zivug—the face-to-face union of consciousness that transcends the limitations of unconscious attachment. When Yom Kippur arrives and the ten-day process concludes, we stand ready not just for forgiveness but for encounter—the meeting between human and divine.
In this light, the shofar blast that initiates the process becomes a love song—the Divine calling us to the delicate surgery that will enable us to truly see and be seen. The Ten Days of Repentance emerge not as a burden of guilt but as a gift of reconstruction, an annual invitation to move from the back-to-back confusion of unconscious connection to the face-to-face clarity of chosen relationship.
This is the deepest secret of nesira: sometimes we must separate in order to truly unite, must cut away in order to heal, must saw through the old to build the new. In the architecture of the soul, destruction and construction are not opposites but partners in the eternal work of tikkun—repair and transformation of ourselves and our world.
[1] Vayikra (Leviticus) Rabbah 14:1 states, “Rabbi Yehoshua ben Rabbi Nechemia and the Rabbis… The Rabbis said: He created him as a golem [unformed mass] and his limbs were stretched from one end of the world to the other… Rabbi Yehoshua said in the name of Rabbi Berekhya: He created him with his [Eve’s] body attached to his side, as it is stated, ‘And He took one of his ribs [מִצַּלְעֹתָיו]’ (Genesis 2:21)—meaning, one of his sides (מִסִּטְרוֹהִי).”
[2] Berakhot 61a states: “”It is written, ‘male and female He created them’ (Genesis 1:27), and it is also written, ‘for in the image of God He made man’ (Genesis 9:6). How is this? Initially, the intention was to create two, but in the end, one was created. It was taught in a baraita: Rabbi Yirmeya ben Elazar said: The first Adam was created with two faces (du-partsufin), as it is stated, ‘You have formed me behind and before’ (Psalms 139:5).” We find a similar passage in Eruvin 18a, which states, “Rabbi Shmuel bar Naḥmani said: When the Holy One, Blessed be He, created the first Adam, He created him with two faces. Then He sawed him and made two backs for him, a back for this one and a back for that one.” The Bereshit Rabbah 8:1 echoes the Talmudic understanding, writing, “Rabbi Yirmeya ben Elazar said: When the Holy One, Blessed be He, created the first Adam, He created him an androgyne, as it is said, ‘male and female He created them’… Rabbi Shmuel bar Naḥman said: When He created him, He created him with two faces (du-partsufin), and He sawed him and made him two.”
© 2025 Alexander Poltorak. All rights reserved.
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