After his conversion, Duran does not, in fact, appear to have become assimilated into the Christian community in which he continued to pursue his livelihood. On the contrary: as we see from his literary works, he remained strongly, even fiercely, committed to preserving the integrity of the Jewish community around him and to asserting his own distance from Christianity. Even the archival record, increasingly sparse as it becomes, suggests a certain level of continuing involvement with the welfare of the Jews of Perpignan. In March 1393, we see Honoratus lending money to a Jewish widow for support of her three children.40 Nearly ten years later, in 1402, he appears as an arbiter in a dispute between two Jews, indicating that he was still esteemed enough by members of the Jewish community to be turned to for fair judgment.41 And as late as 1409, as noted in the Introduction, Honoratus seems still to be in a business partnership with the Jew Cresques Alfaquim.42
Although it has been often thought that Duran returned openly to Judaism in his later years, we have no evidence that he availed himself of this route; instead, what we have is continuous evidence of a public life as a Christian even as, in his writings—in Hebrew and presumably read only by Jews and conversos—he reveals an inner life as a Jew. As archival evidence attests, the man once known as Profayt Duran continued to reside and conduct business in Perpignan as a Christian. And yet during this same period, Duran also composed his two explicitly anti-Christian polemical works: Al tehi ka-avotekha (c. 1394/139543), the satirical letter purporting to be a message of congratulations to David Bonet Bonjorn, a recent sincere Jewish convert to Christianity, and Kelimat ha-goyim44 (1397/139845), a historical study intended to demonstrate that church dogma is incompatible with the teachings of Jesus as found in the Gospels themselves.
Amid the trauma visited upon the Catalonian Jewish community in the late fourteenth century, a particularly demoralizing factor was the voluntary conversion of a number of Jewish figures who then proceeded to work actively and conspicuously on behalf of their new religion. Abner of Burgos (c. 1270–1347), who became Alfonso de Valladolid, had been an earlier prototype; among his other activities aimed at converting Jews, he carried on a polemical correspondence with Isaac Pulgar.46 Another was Solomon ben Isaac ha-Levi, who, as Pablo de Santa Maria (c. 1351–1435), became bishop of Burgos and close adviser to Pope Benedict XIII. Joshua ha-Lorqi, who became a prominent friar named Jerónimo de Santa Fe (fl. 1400–1430), not only polemicized against the Jews but led the Christian side at the 1413–1415 Tortosa disputation.
Our knowledge of each of these cases derives in part from letters exchanged between the neophyte and one or more of his former coreligionists. These letters, written in Hebrew, were “public” documents. Alfonso’s correspondence with Isaac Pulgar (fl. first half of the fourteenth century) and Pablo de Santa Maria’s with the then-still Jewish Joshua ha-Lorqi must have been widely read and discussed.47 Duran’s Al tehi ka-avotekha, addressed to David Bonjorn, was itself such a public letter, and the numerous extant copies of it testify to a wide distribution.48 Nor is it surprising that many of Duran’s postconversion writings reveal a similarly acute awareness of the issues of heresy, voluntary or forced conversion, and the weakening of faith. For these loomed large in his environment and among his acquaintances, and would loom still larger after the Tortosa disputation.49 The culmination of this process was reached in the wake of Tortosa during the preaching activities of Vicent Ferrer (1350–1419), when many more in the Jewish communities began converting to Christianity. In fact, some communities that seemed to have survived 1391 relatively unscathed collapsed at this time, including the aljama of Perpignan, which by 1415 was reduced to a mere handful.50
Duran remained living in his old house, and we see him after conversion collecting old debts, an activity that supplied at least part of his income. The practice of medicine provided another part; some time before May 14, 1398, he obtained the title—available only to Christians—of magister in medicina.51 Both the title and his new status as a Christian would presumably have enabled him to charge more for his services than he could have done as a Jewish doctor. He now also sought further employment in an area in which he was immediately competent: the mathematics and astronomy he had studied and taught previously.
On May 1, 1392, no more than a few months after his forced baptism, the newly minted “Honoratus de Bonafide” was appointed a familiar of Joan I, king of Aragon, in the capacity of astrologer.52 Under Pere III and his successors, astrology, alchemy, and astronomy had become major interests for the royal court in Perpignan. Joan I (“el Cazador”) was known for his passion for hunting but also for his interest in astrology, numerology, and divination.53 Did Duran’s recent conversion now permit the king to offer this kind of patronage? Unlikely, for there is no evidence that Duran’s former religious status would have been an impediment; numerous Jews were associated with the court as physicians or astrologers. But Crescas de Viviers, Joan I’s chief court astrologer, had recently died, in the very riots that had affected Duran. Perhaps there was need for another astronomically competent astrologer. Duran’s title of magister in medicina would have constituted another mark in his favor, for astrology was practiced very often for specifically medical purposes, such as determining the best times for administering medications or letting blood.
Whatever may have been the decisive factor, Duran was evidently skilled in the astronomical techniques needed to practice as an astrologer, as well as in the principles of astrology itself. While he only occasionally alludes to astrological concepts in his writing, we may presume that he was known for this proficiency in at least some court circles. In this connection, one of his students records Duran’s astrologically informed clarification of an obscure comment by Abraham ibn Ezra (1089–1164) on the Bible. According to Duran’s explanation, biblical sacrifices—which presumably mitigated the consequences of negative astrological configurations—were instituted on the new moon, the first day of the month, because it is at the time of the conjunction of the moon and the sun that “the judgments of the lower world are decreed.” Similarly, sacrifices were offered on the seventh day of the month because on that day the aspect of the moon relative to the sun is negative. In addition, Passover and Sukkot—and the sacrifices associated with those holidays—were set to begin on the fifteenth day of the month, when the sun and moon are in opposition, again a negative configuration.54 Similar material appears in Duran’s letter on the number seven (“On the Hebdomad”).
In 1395, Duran completed his first independent treatise, Ḥeshev ha-Efod, a manual on the Jewish calendar. As I discuss in Chapter 7, this text, composed a mere three or so years following his conversion, shows his unabated interest in Jewish issues. The twenty-third chapter, composed in verse form, contains a unique reference to Duran’s Hebrew name, Isaac ben Moses ha-Levi:
And this will be an ordinance for thee for generations until the High Priest stands at the mystery of the Urim and Tummim.
It was composed by Isaac son of Moses, a Levite; his Rock is not like [their] images.55
It is a gift for Moses, great in works, of the house of Hasdai, Levites of the pure ones56
Who will grow and flourish like the palm tree, in his day may the Rock gather the scattered ones,
And the rest of my acquaintances and friends and noble ones and those who listen to me, [the] companions,
May God bring them together to Mount Zion in song and verse, on the wings of eagles.57
These lines, full of longing for the messianic age, invoke an image of the high priest restored to his place in the Temple, arrayed in his sacred garments and “standing at the mystery” of the Urim and Tummim. Duran may be relying here on the exegetical tradition that construed the biblical Urim and Tummim as some sort of astronomical instrument, perhaps an astrolabe, by which the future could be foretold, hence of particular relevance in a treatise devoted to the computation of the calendar.58 And