Know that we Jews have three kinds of books: the first is the Bible, and we all believe in this with perfect faith; the second is called the Talmud, and it is an explication of the commandments of Torah, for there are 613 commandments in the Torah, and every single one of them is explicated in the Talmud, and we believe in this explication of the commandments; and we have also a third book which is called Midrash, which means "Sermons". This is just as if a bishop were to stand up and make a sermon, and one of his hearers liked it so much that he wrote it down. And as for this book, the Midrash, if anyone wants to believe in it, well and good, but if someone does not believe in it, there is no harm....Moreover, we call the Midrash a book of "Aggadah", which means "razionamiento", that is to say, merely things that a man relates to his fellow.
This is from the Vikuah of Nahmanides, an account of a disputation in Barcelona between the great rabbi and Fray Paul before King James I of Aragon. Nahmanides, also known as Moses ben Nahman or Ramban (not to be confused with Rambam, who is Maimonides), was the last great figure in the waning years of what has been called the Spanish Golden Age for the Jews. In Spain, unlike elsewhere, the perpetual conflict between Christian and Muslim had forced both sides to make alliance with Jews. The result on both sides was a flowering of Jewish culture thatwas unrivalled until the Haskallah, or Jewish Enlightenment, and perhaps not even then. It was not a perfect time for Jews. While the Christian-Jewish alliance in Christian Spain (which, of course, was becoming a larger and larger part of Spain through much of the late Middle Ages) gave Jews more room to flourish on their own terms than ever before, it was nonetheless precarious; Spanish monarchs were perpetually under external and internal pressure to enforce the anti-Jewish laws that were still technically on the books. While Jews could and did do very well for themselves, there was always a sort of implicit qualification: they rose to power, wealth, and influence in the way foreigners with needed skills may rise to it.
As Maccoby notes in his discussion of the Barcelona Disputation (which took place in 1263), the fact that the disputation took place at all was a sign of just how far the Golden Age had waned. Nonetheless it is a remarkable tribute to Spain at the time that this Disputation, while not perfectly fair (it was, after all, Catholic Spain, and Nahmanides had to watch his step in a way the Catholics did not), was nonetheless very close to it, and we find in Nahmanides' Vikuah one of the greatest and most courageous Jewish minds of the Middle Ages meeting Christianity head on and not backing down. One of the features of the Disputation is that, while the playing field was Christian, the Jews had an advantage in the debate. At this period in time, the Dominicans were pioneering a new way of seeking Jewish conversion. Instead of preaching at them how stiffnecked they were (which at the time was a surprisingly common approach to persuading Jews to follow Christ), they made an attempt to speak to Jews in their own terms, appealing to the Talmud and to various books of Midrash to argue (abstracting entirely from the question of whether Jesus was the Messiah) that it was possible to establish a Jewish defense of the claims (1) that Messiah had come; (2) that Messiah had to die; and (3) that Messiah had to be divine. While politically the home court advantage always went to the Catholics, this new missionary tactic had the consequence that the terms of the debate favored the Jews, at least in principle. Jewish converts like the Fray Paul Christiani mentioned in the passage above used their pre-conversion study as a jumping-off point for disputing with the Jews.
Of course, the Jews themselves were not inclined to like this much more than any other sort of dispute. They wanted to be left alone; and, since they could not disobey the magistrates who summoned them to these debates, they generally sought as much as they could to evade any direct conflict head on. However, in this one case we have a Jew who felt he could speak more plainly arguing, in front of a monarch who, despite being definitely Catholic, had considerable sympathies with the Jews, many of who he depended on for running his kingdom, against Christian opponents who, while intelligent and learned in their own right, were no match for his genius. It's a fascinating result, particularly since we get Nahmanides's own perspective on the Disputation, and a very firm insistence on the claim that Judaism is a more rational religion than Christianity. We also get interesting cases in which Nahmanides struggles to convey to Christians some insight into aspects of Jewish life -- the primal importance of law, the secondary importance of doctrine, the concepts of midrash and haggadah, and so forth -- that were very foreign to Christian minds. To do so he has to simplify, of course (as he does in the above passage), but, being Nahmanides, he is still able to convey the basic point.
[Translation of passage from: Hyam Maccoby, ed & tr. Judaism on Trial: Jewish-Christian Disputations in the Middle Ages. Fairleigh Dickinson University Press (East Brunswick, NJ: 1982) 115-116.]