This article draws on the analysis of Roman law and on the Jewish tradition of lamentation to offer an original reinterpretation of Nietzsche’s On the Genealogy of Morality. According to Nietzsche, an archetype of a successful revolt against injustice is to be attributed to the Jews—as the ones who were able to carry out “the most spiritual revenge” against the Roman “masters” by transvaluing their values. The analysis of ancient Roman law helps to illuminate Nietzsche’s enigmatic account of the “law of the masters” against which the transvaluation of values takes place. Certain structural elements of the language of lament are then envisioned as a resource for leaving the Roman legal order behind and, surprisingly, for bringing out the very meaning of the modern conception of “rights.”