A Kabbalist in 16th-century Safed dipped his reed pen, drew one word — Ein Sof — then crossed it out and wrote Ain Soph Aur above it. The change was not a spelling error. It was a theological distinction that had taken two centuries of debate to sharpen. The difference is this: Ein Sof (אין סוף) is the divine essence itself — the Infinite, utterly beyond thought, while Ain Soph Aur (אין סוף אור) is the first emanation of Limitless Light, the bridge between the unknowable God and the ten sefirot. One is the source; the other is the first ripple.
Where the two terms were born
The phrase Ein Sof appears in the earliest Kabbalistic texts of the late 12th and early 13th centuries, particularly in the circle of Isaac the Blind (c. 1160–1235) in Provence. The Sefer ha-Bahir, a foundational work of early Kabbalah, speaks of a root that has no end, ein sof, but does not yet treat it as a formal name. It was the Kabbalists of Gerona, especially Azriel (c. 1160–1238), who first used Ein Sof as a fixed term for the concealed Godhead, the cause of all causes that cannot be grasped by any category.
Ain Soph Aur is a later compound. The Zohar, the central text of Kabbalah attributed to Moses de Leon (c. 1240–1305), speaks frequently of the or ein sof, the light of the Infinite, but does not hyphenate it into a single term. The noun phrase Ain Soph Aur emerged in the 16th century, during the great systematization of Kabbalah by Moses Cordovero (1522–1570) and later Isaac Luria (1534–1572). Cordovero used it to distinguish the emanation of light from the essence that emits it. Luria kept the distinction but folded it into his doctrine of tzimtzum, the contraction of the Ein Sof to make room for creation.
For a Kabbalist in Safed, the difference was not academic. It determined how you prayed, how you meditated, and how you understood the first act of creation.
What each term actually describes
Ein Sof means “without end”, no boundary, no limit, no attribute. It is the Ayin (nothingness) from which all things arise, but it is not a thing. The Zohar says: “It is not known and cannot be known; it is the hidden of the hidden.” The Ein Sof has no name, no form, no will. It is the absolute simplicity of the Divine, prior to any relation.
Ain Soph Aur means “limitless light.” It is the first emanation that proceeds from the Ein Sof, not by an act of will but by an overflow of substance. This light is the raw material of the sefirot. It is still infinite, still beyond full comprehension, but it can be spoken of, as light, as flow, as the first trace of differentiation. The Lurianic tradition calls this or ha-ein sof and describes it as the light that fills all possible worlds until the tzimtzum withdraws a portion of it to create a void.
The difference is ontological: Ein Sof is the source; Ain Soph Aur is the first consequence. The one is the ocean; the other is the wave that moves across it.
Why the “light” matters
The choice of the word aur (light) is deliberate. Light in Kabbalah is not a metaphor in the modern sense. It is a substance that carries both revelation and concealment. Light reveals what it illuminates, but it also veils itself, you cannot look directly at the sun.
In the Idra Rabba section of the Zohar, the ancient sages describe the Ein Sof as a “head that is not known” and the Ain Soph Aur as the “white light” that streams from that head. The white light contains all colors in potential, just as the sefirot contain all forms in potential. When the Kabbalist meditates on the Ain Soph Aur, he is not trying to see the Ein Sof, that is impossible, but to align himself with the first outflow of the light before it divides into the ten vessels.
The practical consequence: a practitioner who contemplates the Ein Sof without the mediation of the light is attempting the impossible. The Zohar warns that “to enter the hidden is to be consumed.” The Ain Soph Aur is the permissible threshold.
How the terms are used in practice
In the meditative tradition of kavanot (intentions), the Kabbalist recites the blessing formula Barukh shem kavod malkhuto le’olam va’ed (Blessed be the name of the glory of His kingdom forever) with a specific mental focus on the light. The Ari (Isaac Luria) taught that from the Ain Soph Aur, a single ray, kav, extends into the void left by the tzimtzum. This ray is the channel through which all subsequent creation flows.
When we light the Shabbat candles or bind the tefillin, the Lurianic intention is to draw down a spark of the Ain Soph Aur into the spheres of action. This is not a metaphor. It is a mechanical act: the light is real, and it can be channeled.
In the Pardes Rimonim (Orchard of Pomegranates), Cordovero maps the Ein Sof and Ain Soph Aur onto the first two of the ten nothings, the stages of emanation before the sefirot. The Ein Sof is the first nothing; the Ain Soph Aur is the second. The remaining eight are the sefirot themselves. This is the most precise schema we have.
Ain Soph Aur vs. Ohr Ein Sof: a common confusion
Many texts use Ohr Ein Sof (light of the Infinite) and Ain Soph Aur (Limitless Light) interchangeably. The difference is subtle but real. Ohr Ein Sof is a descriptive phrase, “the light that belongs to the Ein Sof.” Ain Soph Aur is a name, a single term for the emanation considered as a distinct entity.
In the Zohar, the phrase is always or ein sof. In Cordovero, it becomes Ain Soph Aur as a compound noun. Some later Kabbalists, including the Baal Shem Tov, preferred Ohr Ein Sof to keep the emphasis on the light’s connection to its source. Others, like the Vilna Gaon, retained Ain Soph Aur as a technical term. Both are correct in context; the difference is one of emphasis, not of heresy.
Common misconceptions
Misconception 1: Ein Sof is a sefirah. It is not. The sefirot are ten attributes or vessels. The Ein Sof is above them, outside the sefirotic system entirely. It is the cause of the sefirot, not one of them.
Misconception 2: Ain Soph Aur is the same as the Ein Sof. They are not the same. The Ein Sof has no light, no attribute, no relation. The Ain Soph Aur is the first relation, the first light. To equate them is to collapse the entire Kabbalistic hierarchy.
Misconception 3: You can meditate directly on Ein Sof. By definition, you cannot. The Ein Sof has no form, no name, no point of contact. The Zohar is emphatic: “Of it, one can say only it is.” All meditation in Kabbalah is directed at the Ain Soph Aur or the sefirot, never at the Ein Sof itself.
Misconception 4: The tzimtzum happened to the Ein Sof. The tzimtzum contracted the light of the Ein Sof, not the Ein Sof itself. The essence remains unchanged and unbounded. The contraction affected only the or ha-ein sof, the Ain Soph Aur.
FAQ
Is Ain Soph Aur a sefirah?
No. It is the emanation that precedes the sefirot. The first sefirah, Keter (Crown), receives from the Ain Soph Aur but is not identical to it.
Can a beginner practice with Ain Soph Aur?
Kabbalistic tradition holds that one must first master the lower sefirot and the Shemot (divine names). Direct contemplation of the limitlessness is reserved for advanced students under a teacher.
Why is the term “Ain Soph Aur” sometimes spelled “Ayn Sof Or”?
Transliteration varies. The Hebrew letters are the same: ayin-yod-nun samekh-vav-peh aleph-vav-resh. “Ain” and “Ayn” are both valid; “Aur” and “Or” are both standard.
What is the difference between Ain Soph Aur and the Keter?
Keter is the first sefirah, the “crown” that receives the light. Ain Soph Aur is the light itself. Keter is a vessel; Ain Soph Aur is what fills it.
The distinction and its cost
The difference between Ein Sof and Ain Soph Aur is not a footnote. It is the hinge on which the entire Kabbalistic system turns. The Ein Sof is the hidden God, the silence that cannot be broken. The Ain Soph Aur is the first sound, the first light, the beginning of the world that can be spoken of. To confuse them is to lose the logic of emanation. To hold them separate is to understand why Kabbalah is a tradition of limits, of what can be said, what can be seen, and what must remain untouched.
If you are ready to go deeper, we have mapped the ten sefirot in detail, and we have traced the three veils of negative existence in the Kabbalist cosmos. The Kabbalah hub is the starting point. For the exact terms, see the glossary entry for Ein Sof. And for the system that builds on these two concepts, the guide to the Sefirot is the next step.