Abstract: The Liber vagatorum, a popular Rhineland work printed in 1510, warns against abusive begging. It proposes a typology of beggars and a glossary of mendicant slang, the Rotwelsch, including many Hebrew words. What reasons led Luther to republish this work in 1528? Beyond a warning against the devil’s actions, the republication of the Liber vagatorum must be seen in the context of Luther’s relations with the Jews and contemporary Judaism.