Reviewed by: The Secret Faith of Maestre Honoratus: Profayt Duran and Jewish Identity in Late Medieval Iberia by Maud Kozodoy Rebecca Lobel Kozodoy, Maud, The Secret Faith of Maestre Honoratus: Profayt Duran and Jewish Identity in Late Medieval Iberia (Middle Ages), Philadelphia, University of Pennsylvania Press, 2015; cloth; pp. 336; R.R.P. US $59.95, £39.00; ISBN 9780812247480. Maud Kozodoy’s study of Profayt Duran reveals a compelling portrait of a late fourteenth-century Spanish physician, astronomer, and philosopher whose works were defined by his Jewish intellectual roots. Assuming the Christian name Honoratus de Bonafide after his forced conversion in 1391, Duran served as court physician and astronomer to King Joan I of Aragon: a public display of his professional talent in the most prestigious sciences of the time. Privately, though, Duran wrote under the Hebrew pseudonym Efod, producing a wide array of texts, primarily anti-Christian polemics, which were intended specifically for a Jewish or converso audience. Through a sophisticated exploration of his works, Kozodoy offers a concrete analysis of Duran’s legacy and – most importantly – his philosophical position on the collapse of Iberian Jewry in the wake of unprecedented persecution. Writing exclusively in Hebrew, Duran’s works are a glimpse at the regular exchange of ideas within Spanish Jewish intellectual circles through the circulation of epistles and manuscripts. Any enthusiast of medieval philosophy, medicine, or mathematics will enjoy this aspect of Kozodoy’s book, as the works of Duran are a profound synthesis of both Christian and Jewish approaches to science. Those interested in conversos will also enjoy it, since Duran’s biography, explored in Part I, is in many ways typical of a Catalonian Jew; forced to adapt outwardly as a New Christian, Duran covertly nurtured a deep and evolving Jewish identity, as demonstrated by his scholarly works. Steeped in the rationalist philosophical tradition of Maimonides, Duran used the virtue of reason to privilege science over other means by which to understand his world. Kozodoy shows Duran’s intellectual approach in Part II through compelling case studies, including his adept use of geometry and astronomy to create Heshev ha-Efod, a superb lunar and solar Jewish calendar designed specifically for use by conversos. Duran’s essay on the number seven as mispar kolel, a perfect number, is also fascinating; when Kozodoy compares it to Oresme’s similar Christian treatise on the number three, it becomes clear how each thinker used arithmology to prove the verity of their religion through the evidence of numerical patterns in Creation. These works are [End Page 222] decidedly polemical, an attempt by Duran to show the accuracy and truth of Judaism over Christianity through mathematics and philosophy. Duran’s literary works share the same polemics displayed in his more scientific treatises. Kozodoy demonstrates this through her analyses of Duran’s satire Al tehi ka-avotekha (‘Be Not Like Your Fathers’) and the epistle Kelimat ha-goyim (‘The Disgrace of the Gentiles’), which both critique Christian theology as irrational and philosophically erroneous. Duran refutes Christian themes including the Trinity, the Virgin Birth, and the divinity of Jesus through informed and cautious study and articulate rebuttal. As Kozodoy notes, there is evidence that Duran learned Latin and used it in his study of the Gospels, showing his mastery of Christian doctrine from within the tradition. It is difficult not to be impressed by Duran’s ability to navigate both Jewish and Christian society, religion, science, and philosophy; a survival skill acquired, most unfortunately, against his will as a forced convert. Part III covers the last surviving texts of Duran, which are, according to Kozodoy, the most important and most evolved. In both Eulogy for Abraham ha-Levi of Girona and Ma’aseh Efod (‘The Works of Efod’), Duran establishes the central importance of kavvanah, or spiritual intention, given the woeful inability of most conversos to participate in Jewish rituals or observance. This preference for ‘wisdom’ over ‘deed’ (p. 163) and the spirit over the body privileged Torah study over ritual performance, giving conversos practical instructions to keep hope for a future where they might be able freely to return to Judaism. Kozodoy notes Duran’s characterisation by seventeenth-century Rabbi Joseph Delmedigo...