An analysis of the portrait of Otto Lenel offered by Hugo Sinzheimer in his Jüdische Klassiker der deutschen Rechtswissenschaft (Jewish Classics of German Juris-prudence), published in 1938, allows us to reflect critically in a broader context on anti-Semitism in German culture between the 19th and 20th centuries. This analysis gives us an opportunity to unearth the roots of the prejudices which, even in the academic world, were used to justify a position incompatible with the task of their profession to cultivate the progress of science through the objective verification of every assertion.