Blurb:

When contemporary historians and sociologists discuss Jewish identity, they often tell a tale of decline. Once upon a time, everyone knew who was Jewish and who wasn’t. Though some people converted, and some Jews occasionally passed as non-Jews, the lines between Jew and non-Jew were visible and agreed upon. Then came emancipation and its unfortunate companions assimilation and intermarriage, and thus Jewish identity became diffuse, partial, and mixed. This decline narrative suggests the loss of a stable center of Jewishness. Jewish Studies scholars might valorize certainty and stability of Jewishness for a variety of reasons—the analytical appeal of certainty, a holdover from the centrality of objectivity in the origins of Jewish Studies, or even a theological desire for clarity about who is a Jew. But a close look at antiquity shows us that “Jewish identity” has long been diffuse and mixed. The intensity of the Jew/Judean translation debate also suggests that scholars cannot decide whether the ancient ioudaioi were religious or national. And for good reason: these ioudaioi do not neatly fit into one of these established categories. Like the second-century rabbinic discussions about the fictional animal called a koi, they were sometimes one, sometimes the other, sometimes both, and sometimes neither. In the end, the ancient material suggests that Jewishness had—and has—no stable essence.