This work is about a mishnah and its gemara that are woven into the talmudic Tractate Sanhedrin, mSanhedrin8:7 (bSanhedrin73a-74b). The mishnah stipulates that one may legitimately kill a “pursuer,” that is someone, who is about to commit a severe transgression of the law. What legitimizes the killing of the pursuer, however, is not the life-saving effect of his death, but his transgression: The pursuer may be killed, because his death saves himself from crossing a line that separates an area, within which a Jew’s life is deemed possible, and beyond which life is possible in a mere physical sense. When identifying the specific acts that turn a Jew into a “pursuer,” the tannaim thus struggle to define and separate the “livable” from the “non-livable,” culture from nature, law from lawlessness, a sphere infused, governed and legible via a halakhic idiom, from an abyss beyond the latter. In the course of this work, the mishnah will be read in two larger textual frameworks: the gemara to mSanhedrin8:7, and the Babylonian narrative traditions, that depict an encounter between a Jew and his or her political and/or religious antagonist. In both these frameworks, the question underlying mSanhedrin8:7 –“what is a Jew to die for?” – is transferred to a situation of political, systematic persecution; specifically, to a situation, in which a tyrant forces a Jew to either transgress and to live, or to avoid a transgression and to die. Here, a technical, clear-cut differentiation of acts into “permitted” and “forbidden” proves to be impossible: In a world turned upside down by persecution, the boundaries of the Jewish collective, both physically and ideologically, become fragile. Their maintenance requires reflection about the nature and meaning of these boundaries and their transgression, about the impact of persecution on a transgression, and the identity of the Jewish community itself. The definition of those acts a Jew is to “die for”t hus becomes a vehicle through which the authoritative claims of the divine law and its constitutions of the Jewish social body, are both contested and erected.