"Listen, all you peoples, to the shame and the disgrace which these Jews committed on our Saviour Jesus, in that, for no crime of his, they afflicted him and killed him and hanged him and tortured him,” declaimed the Dominican friar Paul Chrétien to a large audience of Christians and Jews near the university of Paris in 1273. He had once been Jewish himself (known then as Saul of Montpellier) but now, with all the savage zealotry of an apostate, he pointed at the rabbis debating with him and yelled, “They deserve to be killed, just as they killed him.”

He quoted from the Mishnah, the Talmud, halacha (rabbinic law), and haggadot (rabbinic lore) to show that the Jews had always known that Christ was the Messiah. “I wish to prove to you,” he said to the rabbis with sadistic reasonableness, “that you are without a faith, a people called Bougres — heretics worthy of being burned.”

Everyone listening knew that Bougres was just another name for the Albigensians, the supposed heretics massacred in the tens of thousands by northern French crusaders during the notorious Albigensian crusade in southern France from 1209-1229.

Rabbi Abraham ben Samuel refuted Paul Chrétien’s arguments with learning and wit, winning over the crowd, but once the latter invoked the crucifixion he was, according to an anonymous Jewish chronicler, “very much afraid to speak of the slaying of Jesus because this revealed his adversary’s resolve to exterminate all of the Jews”.

And so the debate abruptly ended, everyone quickly dispersing, although cruelty and fear lingered awhile longer on the Left Bank.

Three decades earlier, and not too far away from where Paul Chrétien and Abraham ben Samuel would eventually debate, 24 cartloads of the Talmud were incinerated as books of heresy in a great bonfire in Paris in 1242. Once again, another Jewish convert to Christianity, Nicholas Donin, led the attack. He accused his former co-religionists of deliberately elevating the Talmud over the Bible as a way of avoiding acknowledging that they were and should be Christians.

Rabbi Meir ben Baruch of Rothenburg, who witnessed the burning of the holy books as a student in Paris, later lamented in a poem:

How were you given over to a consuming fire?
How were you devoured by man-made flames and the oppressors not scathed by your coals?

Thirteenth-century Christians (newly converted or not) accusing Jews of being heretics was a consequence of the belief in Latin (or Western) Christendom that Jews, far from having a different religion, were essentially Christians and so, in their refusal to acknowledge this reality about themselves, were heretics.

These accusations were a consequence of the belief among medieval Christian intellectuals that Christendom encompassed all time and space and so anyone who had ever lived and would live had the revelation of Christ and so was Christian whether they realised it or not. A person not accepting this understanding of the universe and themselves within it was a heretic. Jews in particular, but also Muslims and even the Mongols, were accused by popes and kings of being heretics.

This all-encompassing vision of Christendom was most powerfully articulated by Pope Innocent III around 1200. It was most artfully encapsulated in Dante Alighieri’s Divine Comedy a century later.

This vision was connected to a new sense of what it meant to be human that had been developing in the West since 1100. An individual life was now assumed to move forward through time in a series of interconnected events, actions and thoughts. The crawling child inescapably led to the elderly adult. This initially resulted in an explosion of men and women writing autobiographies for the first time in seven centuries.

By 1215, all Christian men, women and children were required to confess once a year to a priest. They were required to talk about themselves as if what they did and thought in the past was intimately connected to what they were thinking and doing in the present and what they would go on to think and do in the future. This new confessional culture defined the late Middle Ages.

Now, this might sound an awful lot like what most modern Western people think about themselves, if they give any thought to it at all. That surely who I was as a child has some unbreakable intimate connection to who I am now as an adult. That the living of a life can be narrated as a linear story that we tell ourselves and that can be told to others. That our identity as humans moves forward in time, experiencing new things, while our memories trail behind us. And that this all seems natural. It is not. This distinct sense of the self was created in the 12th and 13th centuries of the medieval West.

Intimately connected to this new sense of the self was a new obsession among medieval Christians with the life of Christ from the late 11th century onwards. His existence as a human in the New Testament — and here the crawling child inevitably led to the crucified adult — was something that could be imitated by princes or peasants. The First Crusade proclaimed by Pope Urban II in 1095 is not only explained by this growing obsession but helped propagate it throughout Christendom.

This enthusiasm for Christ inflamed some thuggish crusaders — the “leftover shit” as one monk denounced them — into attacking Jews in the Rhineland in 1096. (Most of these “shitty” thugs were soon killed in the plains of Hungary, cut down by locals infuriated at their brigandry and violence.)

These Rhenish assaults were the first attacks against Jews in the West since the late Roman Empire. None of the assailants justified their brutality by claiming Jews were heretics.
Similar violence against Jewish men, women and children mostly disappeared until the 13th century when they came to be identified as heretics. Until then, only Christians were accused by monks and popes of heresy. Such accusations functioned as admonitions, acts of spiritual guidance, and rhetorical threats.

As far as the Church was concerned, too many Christians failed to grasp that what they thought was right and proper was actually heresy. The Cistercian monk Bernard of Clairvaux described heresy as a cancer, so that while everything on the surface seemed healthy, an individual was being secretly corrupted from within.

Indeed, when Pope Innocent III proclaimed the Albigensian crusade against the heretics who he said were swarming in southern France — including Montpellier where Paul had grown up as Saul — he argued it was an apocalyptic necessity as they were infecting Christendom with their cancer and if they were not “exterminated” then all Christians, including himself, would be similarly diseased.

Yet the pestilence of heresy was not erased by two decades of holy war, and so Pope Gregory IX asked the Dominicans to undertake inquisitions to hunt out heretics in 1230 and 1233. (Nor surprisingly, he was persuaded by Nicholas Donin’s arguments about the Talmud as a book of heresy.) Despite popular misconceptions, the medieval inquisition did not interrogate Jews (or supposed witches) until around 1300 — and then only as heretics as understood by a soapbox sadist like Paul Chrétien.

Anti-Judaism is the term most medieval historians use when referring to the discriminatory rhetoric and brutal fantasies of Christians against Jews throughout much of the Middle Ages, especially before the 13th and 14th centuries. This is to make a distinction from modern antisemitism.

But can we see this shift into what may be classified as eliminationist antisemitism happening in the attacks on Jews as heretics?

It was only when medieval Jews were labelled as heretics by Christian persecutors that they, like other heretics, were to be expunged as a plague and cancer from Christendom.

One of the more unexpected continuities from the Middle Ages is the modern Western sense of self and what was fundamental in its creation was the violent and cruel persecution of Jews as heretics.

Mark Gregory Pegg is a Professor of Medieval History at Washington University in St. Louis. His Beatrice’s Last Smile: A New History of the Middle Ages is published by OUP