By Carol Symes, University of Illinois Urbana-Champaign
How did the fear of Jews as bloodthirsty murderers of Christian children mix with medieval anti-Semitism? The answer is tied up with the wide-reaching implications of a coeval doctrinal development that was creating new anxiety about blood. In the 12th century, the Roman Church began to promote a new focus on the sacrament of the Mass: the ritual reenactment of Christ’s last meal with his disciples.

The Doctrine of Transubstantiation
The celebration, also known as the Eucharist, had always been an important part of Christian worship, but it was now freighted with a new significance promulgated by the powerful preacher Bernard of Clairvaux: the doctrine of transubstantiation or the Real Presence.
According to this doctrine, every Mass is a miraculous event because the priest’s blessing transforms the material substances of bread and wine, placed on the altar, into the actual body and blood of Christ; hence the term transubstantiation, since earthly substances become the substance of Christ’s divine body, his real presence.
Popular reverence for the Eucharist became so great that the Church initiated the practice of elevating the consecrated bread, known as the Host, during the priest’s blessing, so that the whole congregation could see it. Not incidentally, this new theology of the Eucharist further enhanced the prestige of the priesthood by seeming to endow it with wonder-working powers.
In later centuries, the Latin words spoken at the consecration of the Host—Hoc est enim corpus meum (This is my body)—were understood as a magical formula, hocus pocus. To consume one or both of these substances was therefore to ingest holiness.
Fear of Jews Killing Baby Jesus

When this new doctrine and popular religious practice collided with the cloud of anti-Semitic tropes that had already been released into the ether, it gave rise to the fear that Jews would naturally extend their torture of Christian children, who were proxies for Jesus Christ, to the Eucharistic Host.
This fear was stoked by popular artistic representations of transubstantiation, which showed either a tiny baby Jesus or a tiny crucified Christ, miraculously appearing on the altar in place of the bread and wine. By the 13th century, many medieval Christians believed that Jews were stealing consecrated Hosts and thus subjecting Christ’s body to new torments.
This article comes directly from content in the video series The Medieval Legacy. Watch it now, on Wondrium.
Medieval Anti-Semetic Tropes
What the historian Miri Rubin has called “the narrative assault on medieval Jews” thus extended and amplified anti-Semitic tropes, inserting them into the burgeoning vernacular literature of medieval Europe and displaying them on the walls of churches and in stained glass, and enacting them in popular plays—the most potent public media of the Middle Ages.
In the 12th century Anglo-Norman “Play of Adam”, a character simply called ‘The Jew’ is a wily intellectual who engages in a dispute about the Virgin Birth and nearly manages to disprove it. In a contemporary Christmas play from Bavaria, Herod is advised by a counselor who shows that the attributes of a “stock” Jewish character had already developed. According to the play’s stage directions, the actor playing this Jew should waggle his fingers and stamp his foot, nodding his head sycophantically, and “imitating the manners of a Jew in all ways”.
By the later Middle Ages, even more virulently anti-Semitic types were being staged: Judas wears the Jewish badge and has a long hooknose, demonic Jews rejoice at the Crucifixion. In England, troupes of traveling players would perform dramas like the “Croxton Play of the Sacrament”, in which a group of Jews steal and torture the Host, only to be baptized by Christ in the flow of his blood.
The Jewish Massacre in Tàrrega
This medieval narrative assault coincided with further instances of anti-Semitic violence driven by the great famine of the early 14th century and the Black Death that followed it. In 2014, a team of scholars in Catalonia published archeological evidence of a pogrom against the Jews of a small town called Tàrrega, west of Barcelona, a massacre that is also attested in royal administrative records—the first time that archeological and textual evidence corroborate one another to document a local genocide.
Note the repetition of the anti-Semitic pattern that had, in just about four centuries, been established in medieval Europe: external crisis as a spur to xenophobia, followed by accusations of Jewish treachery, the use of violence as a pretext for robbing Jews of their “ill-gotten” gains, and their slaughter.

Although prosperity would return after the Black Death, successive waves of plague—which became endemic in Europe—would offer new opportunities for Christians to foment violence against their Jewish neighbors. In the 16th century, the deadly litany of anti-Semitic tropes would be available and reusable as unifying forces within the riven Christianity of the Reformation and counter-Reformation, after which they would be exported around the globe.
For, like the plague, anti-Semitism can lie dormant for a while, only to break out with devastating vigor, as in the Q-Anon conspiracy theories of the present day. It’s to be hoped that the more we know about how it became rooted in medieval society, the more we can do to eradicate it now.
Common Questions about How Medieval Anti-Semitism Became Rooted in Popular Consciousness
The doctrine of transubstantiation suggested that the sacrament of the Mass was a miraculous event because the priest’s blessing transforms the material substances of bread and wine into Christ’s body and blood.
Medieval anti-Semitism suggested that Jews were trying to find Christian children to torture. Now that the Christians were turning bread and wine into the blood and body of Christ, they were sure that Jews would try to sabotage the process.
Medieval anti-Semitism started to show itself in plays such as the 12th century Anglo-Norman “Play of Adam” which had a character named ‘Jew’. While another Christmas play from Bavaria has a character with Jewish stereotypes written into its stage directions.