On one point many historians have agreed: the Church’s policies toward Jews remained relatively benign through this period, thanks to the rationale for the preservation of Jewish lives known as the “witness people doctrine,” attributed to Augustine (354-430 c.e.). His view that the Jews were necessary if reluctant witnesses to Christian truth, and worthy of preservation, presumably shaped medieval theologies and ecclesiastical practices from the sixth to the thirteenth century. This paper argues that claims for such a doctrine overstate the influence of Augustine’s occasionally irenic statements on Jews and Judaism and understate the legacy of his negative, deprecatory statements. Evidence suggests Augustine’s conception of the role of Jews as “witnesses” was revived in the twelfth century only after centuries of neglect. It had far less impact than works accepted by medieval audiences as authentically Augustine’s but now regarded as pseudonymous. By investigating evidence from a variety of settings and sources, my paper demonstrates that the twelfth century’s “Augustine” was in fact a source, if not a cause, of markedly heightened anti-Jewish rhetoric. This reappraisal challenges the conventional view that Augustine’s influence restrained Christian hostility toward Jews up until the twelfth century and that hostilities were unleashed in the thirteenth century because that influence had diminished.