PERHAPS NO RELIGION has as much existential uncertainty baked into the product as Judaism. Who, or what, is a Jew? The question remains Jewishness’s most persistent quandary. In modern times, this has not only been a theological or anthropological question but also a political and military one: leaders as diverse as Adolf Hitler and David Ben-Gurion have sought to develop criteria that may nail down Jewishness as something discrete, distinctive, and susceptible to legislation. But still some confusion persists, some hazy aura around the edges of Jewish identity, evident in the thousand and one sects and offshoots and private credos that, collectively, constitute “the Jewish people.”

Enter Amos Oz — one of Israel’s greatest writers, a frequent Nobel contender, author of marvelous works like the memoir A Tale of Love and Darkness and the novel My Michael, and a cofounder of the activist organization Peace Now — and his daughter Fania Oz-Salzberger, a historian and professor at the University of Haifa. In their “little book,” Jews and Words, father and daughter argue that the Jews are best understood as a people with a shared literary history. “Ours is not a bloodline but a textline,” they proclaim. “Jewish history and peoplehood form a unique continuum, which is neither ethnic nor political.” In other words, Jews are not first and foremost a race or a religion but a civilization, one linked by the texts they read, the stories they tell, and the history they’ve chronicled.

This is not a wholly original argument. Some Jewish thinkers, particularly in the last 150 years, have attempted to detach Jewishness from its religious roots, creating humanistic, cultural, secular, or literary strains of Judaism that can be appreciated apart from matters of commandments or belief in the Almighty; examples range from Theodor Herzl’s secular Jewish nationalism to Ahad Ha’am’s cultural Zionism. Eliezer Ben-Yehuda, the person most responsible for the contemporary revival of Hebrew, thought that the propagation of the Hebrew language was less a holy responsibility than a means of uniting the Jewish people into one polity. And many members of the yishuv — Jewish settlements in pre-state Palestine — migrated there not for religious reasons but out of a desire to return to the history-rich lands of their ancestors.

Jews and Words engages some of these forebears (the authors particularly admire Ben-Yehuda), but it is distinguished both by the clarity of its authors’ arguments and the intellectual panache they display on the page. It’s a little book, perhaps, but also an uncommonly delightful and learned one, bringing together (sometimes in a single paragraph) Yiddish poets, Renaissance-era Italian scholars, ancient shepherds, and ghetto dwellers as part of one great textual canvas. It’s a book that will give comfort to the faithless and jab at the certitudes of the faithful. (That it’s written in English — a second language for both writers — adds a grace note of triumph to the affair.)

In Jews and Words, Oz and Oz-Salzberger argue that, over the course of their history, the Jews have created “a trove of referential buildup,” a “genealogy of familiarity that is unique,” the same stories, the same blessings, the same tales of woe, all repeated ad infinitum in a language virtually unchanged for millennia. The...