For about half a century, David, my daily chevruta and I, have met with a constancy that has outlasted careers, relocations, and the relentless pressures of life. David made his life in the structured, exacting world of mathematics; and I, in the lived, unpredictable realities of biology and medicine. We entered adulthood along different paths-one oriented toward abstraction and proof, the other toward the immediacy of the human body and its fragility. And yet, across those differences, we returned-again-to the same texts, the same conversation.
What began as a commitment became rhythm; what became rhythm became structure; and what became structure became, imperceptibly, a shared life in time.
For years, I thought we were simply keeping a schedule.
We met daily, as we always had, at fixed times, anchored by the quiet certainty that no matter what else shifted in life, this would not. The pages and the texts changed, but the meeting or the scheduled call remained constant. It was only gradually that I came to understand that this constancy was not incidental. It was formative. What we had created was not merely a routine.
There are relationships that unfold within time, and there are those that reconstitute time itself. Fifty years of chevruta does not merely accumulate duration; it interrogates the very categories by which duration is ordinarily understood. What appears as a biographical fact-half a century of shared study-reveals itself, upon reflection, as a sustained experiment in the construction of temporality.
Our beginnings were unremarkable. Two students, seated across from one another or via phone, bound by text and obligation. We met at fixed hours, advanced methodically, measured progress in pages and tractates. Time was external, structured-what philosophy calls chronos.
Our differences go back even further than our professions. I grew up with very little, the child of religiously observant Holocaust survivor parents in a small apartment near the Carmel Market in Haifa. Life was immediate, noisy, practical, but often uncertain. From that world a desire for academic pursuit, biology, and medicine emerged.
David was raised in Moscow, in an atheist home shaped by academic life, the son of intellectual parents and grandparents for whom rigorous academic thought were part of daily existence. From that world emerged a remarkable path: David would go on to become a mathematician of the highest order, contributing to fields of representation theory, later continuing his ground breaking work in the United States and Israel; David chaired the Mathematics department at Harvard and was the recipient of many awards; the MacArthur Foundation Prize, Israel Prize, the Shaw International Prize and other honors.
And yet, alongside that intellectual formation, there was another journey for David-but no less decisive. Raised at a distance from Jewish religion, he began in his early twenties to rediscover his Jewish identity and religion, not as inheritance but as choice and by the time he arrived with his family to the United States in the early 1970’s he had become a lamdan- a learned Talmid Chacham as he was described by Rabbi Joseph Soloveitchik.
We came from different languages, different assumptions, different starting points. We met at Rabbi Soloveitchik’s community in Brookline Massachusetts while pursuing our academic careers at Harvard University and Harvard Medical School and even in those early years, something deeper had begun.
For what appears as repetition is never merely repetition. Each return to the text carried with it a subtle transformation, both of the material and of ourselves. The French philosopher Henri Bergson distinguished between time as it is measured and time as it is lived-durée, in which the past is not left behind but carried forward, reconfigured within the present.
Our chevruta, over time, migrated from the domain of chronos into that of duration.
This transformation can be precisely understood through the lens of ספירת העומר, the counting of the Omer-the counting of the forty-nine days between Pesach and Shavuot. Between the Exodus from Egypt and the receiving of the Torah at Sinai.
And we find ourselves now within that very count, in the midst of ספירת העומר, moving day by day toward Shavuot. Each evening, the number is articulated again, and again, and again-another day gathered, another moment shaped, another step taken toward something not yet fully realized. The Rav, Rabbi Joseph B. Soloveitchik was known to emphasize a subtle but deeply revealing nuance in the formulation of Sefirat HaOmer: one counts not only “today is the fifth day to the Omer," but also, in a profound sense, “today is the fifth day in the Omer." In the Rav’s community in Brookline both forms were recited in the daily count. The distinction is more than grammatical. To count to the Omer suggests reference to the starting point on Pesach while counting in the Omer transforms the period itself into an inhabited structure.
Each day is counted, named, fixed. Nothing could be more aligned with measured time. Yet, as the Rav taught, counting in halakhic consciousness is never merely quantitative. Counting ספירה is an act of formation. Each day is not simply recorded-it is constructed into a movement toward meaning. In an address on the concept of time in halacha which the Rav delivered in Brookline in 1973 he stated: “When one counts, one ushers in a continuum".
Chronos is not eliminated-it is redeemed.
In the language of Kabbalah, these forty-nine days unfold through the sefirot-the divine attributes-with each day expressing a distinct inner configuration: ḥesed (loving-kindness) within gevurah (discipline), tiferet (harmony) within hod (humility), -until time itself becomes articulated, textured, alive. No day is interchangeable and each day carries a tone, a quality and direction. Time becomes form and studying in chevruta mirrors this structure. Each session is discreet, yet none stands alone. The early years are not past; they are active, shaping each new encounter. Each session is like a note in a symphony.
A single musical note in a symphony vanishes instantly. But within the composition, it resonates-carrying what came before and anticipating what will come after. It is not isolated; it is situated within a living whole. So too with chevruta learning.
One such session stands out.
There was something almost surreal about our chevruta session at the Institute for Advanced Study in Princeton in 1996 - something that had probably never occurred there before. This was the institution where figures such as Albert Einstein, and J. Robert Oppenheimer, worked and transformed modern thought. The institute’s mission statement proclaims: “The Institute for Advanced Study is one of the few institutions in the world where the pursuit of knowledge for its own sake is the ultimate raison d'être. Speculative research, the kind that is fundamental to the advancement of human understanding of the world of nature and of humanity, is not a product that can be made to order. Rather, like artistic creativity, it benefits from a special environment."
David had been invited there to pursue advanced mathematics and string theory, yet when I entered his office, alongside the papers and equations were shelves lined with volumes of Talmud, Rishonim, and halakhic texts. In that setting, so deeply identified with advanced scientific inquiry, the familiar cadence of traditional Torah study unfolded quietly In that office, two ancient traditions of disciplined inquiry - the Beit Midrash and the modern research institute - briefly converged in a single intellectual and spiritual space.
Each session contains within it decades of prior conversation. Each exchange is shaped by accumulated language and intuition. And each one projects forward, quietly determining what is yet to unfold.
This is not chronology. This is composition.
And like any complex musical composition, it has not been without tension.
There were years of intensity and years of challenge. Moments of clarity and moments of frustration. Life intervened-responsibility, distance, crisis, war, the quiet but persistent pressures of time itself. And yet, through these different experiences of time, we returned to a shared one.
There were periods when the rhythm felt less certain when continuity seemed fragile.
And yet, we returned.
Reaching fifty years-a yovel of learning-brings with it an awareness that is both subtle and profound. One becomes conscious of time not only as something that has passed, but as something that has been shaped. The years are not simply behind us; they are within us. And with that awareness comes gratitude. Immense gratitude.
Not only for what has been learned, but for the presence of another who has shared this time, this wondrous voyage. Chevruta, in this sense, is not simply a method of study. It is a covenant of time. It refuses to allow time to dissolve into isolated moments. It gathers, sustains, and deepens it.
If the forty-nine days of the Omer represent the disciplined construction of time, then the fiftieth represents a threshold beyond counting-a moment in which time is no longer measured, but inhabited.
Fifty years of chevruta is such a moment.
Not an ending, but a gathering.
Chevruta sessions, like the counted days, like the notes of a symphony, have not merely accumulated.
Fifty years of chevruta is not a record of time spent.
It is the lived experience of time transformed.
Let it serve as a luminous model for genuine companionship in an age increasingly defined by digital friendship.
Dedicated, in enduring friendship, love, and profound esteem and admiration to my chevruta, Professor David Kazhdan, whose intellectual companionship has been a source of continual inspiration.
Itzhak David Goldberg is a Professor Emeritus at Albert Einstein College of Medicine