Medieval Christian understandings of the historical relations of the three religions also emphasize the dangerous proximity of Christianity's "others." Of course, the histories of Judaism and Christianity are genetically linked. Yet, from the Christian perspective, the great historical rupture of Christ's incarnation, along with the Jews' rejection of the "truth" of that event, made necessary an intense disavowal of Jewish connections. Those Jews who did not choose to follow Christ's lead violently absented themselves from salvific history; their rejection of Christ became the emblem of an obstinate refusal to see the "truth," the very antithesis of Christian belief. This historical relation is exactly reversed in at least one major medieval understanding of the relation of Islam to Christianity: instead of a new "truth" that fulfills and replaces an incomplete understanding of "truth," as in Christianity's narrative of its own birth from Judaism, Islam is depicted as a monstrous birth out of Christianity, a "heretical" fall from revelation.  The rejection of Christian doctrine by both Islam and Judaism, by supposed "descendent" as well as "ancestor," holds special power because it is in each case understood to arise from a position of intimate (genetic) relation. Not just independent religious traditions that, from a Christian perspective, have "misunderstood" metaphysics, Judaism and Islam plot out two courses of spiritual understanding closely linked to the Christian, and thus, in the logic described by Jonathan Dollimore as the "paradoxical perverse," liable to be demonized in an especially anxious and hostile manner. 
Guibert's fullest treatment of this sort is his account of Jean of Soissons, "a Judaizer and a heretic" (II.5; 136).  Jean's mother "poisoned her own brother through greed for his country," acting "with the help of a certain Jew." This bodily attack is met by appropriately physical punishments. "[T]he Jew [is] burned," while the countess undergoes a debasement of her body at least partly explained by its association with Jewishness: "paralyzed," "infirm," mutilated, she finally becomes mere body, uninformed by "understanding," animal rather than human (III.16; 209- 10).
Jean himself, in Guibert's view, is "worse" than his mother. His crimes, often sexual ones, committed with a body that Guibert describes as "disgustingly scabby," are, like his mother's, closely affiliated with Jewishness: he "practic[es] the perfidy of the Jews and heretics," participating in Christian rituals only because these offer the "pleasurable" opportunity to be with "beautiful women." Jean does "not except nuns or holy women from his abuse," claiming, in a formulation often attributed to "heretics," that "all women ought to be in common" (III.16; 210-11).  His sexual desires are decidedly "dirty" and "perverse," and facilitated by a Jew:
Although he had a pretty young wife, he scorned her and was in love with a wrinkled old woman. He had a bed in the house of a certain Jew and often had it laid out for him, but he could never be restricted to a bed and, in his raging lust, thrust himself and that filthy woman into any foul corner. (III.16; 210-11)Like his mother, Jean is punished through the body for his abuse of body:
When the Virgin Mother, Queen of all, could no longer endure the blasphemies of this corrupt man, a great band of his brothers, the devils, appeared to him. . . . Coming home with his hair disordered and out of his wits, he repulsed his wife that night and lay with [concubuit] that old woman. That night he fell ill [decubuit] of a mortal disease. (III.16; 211)In his last hours, Jean like his mother, enters a state of "delirious" irrationality. His bodily illness now threatens to extend beyond himself, into a violence against others, and like the devils associated with his disease or like a wild animal, he must be restrained (III.16; 211).
Significantly, the account of Jean's life leads directly into a broader discussion of the "heresy" Guibert sees as flourishing near Soissons, central to which are bodily corruptions, the burning alive of an infant and the consumption of its ashes "as a sacrament," and sexual "perversions": "you may see men living with women without the name of husband and wife in such fashion that one man does not stay with one woman, each to each, but men are known to lie with men and women with women, for with them it is impious for men to go to women" (III.17; 212-13).6
In this and other episodes of the Memoirs involving Jews, we can see Guibert developing a complex definition of the righteous Christian self. "Heretical," "blasphemous," and "Judaizing" tendencies associated with the devil; an involvement in physical- ity that expresses itself in violence and in a strong, often "perverse" sexuality; the loss of bodily integrity that follows on dedication to the physical; an abandonment of rationality; the descent into an animal realm particularly associated with women's bodies (Jean's mother comes to lead "the life of a pig")--all that must be excluded from the Christian self is revealed in those instances where Christians give in to the influence of Jews.
While Guibert directly examines the violent behavior and "disgusting" bodies of Christians who violate the boundaries of "proper" behavior and body, he keeps the Jews who are their accomplices largely unrepresented, relegated to auxiliary roles. If Christians who fall under Jewish influence represent, in their "perverse" behavior, what is imaginable, tempting, but disallowed in the struggle to shape a proper Christian self, the Jewish figures who lead Christians away from such a self occupy a certain "beyond" that Guibert chooses never fully to represent. If, as it seems, to be in contact with unconverted Jews is already somehow to have stepped outside the Christian community, to have moved toward the "underground vaults" and "unfrequented cellars" of "heretical" activity (III. 17; 212), what it means actually to be a Jew is never here imagined.
The representation of Christians seduced by Jewish proximity leads to a certain destabilization of Christian identity. But the decision not to represent Jewish individuals in any detail creates an identity position fully outside the Christian, against which Christian identity may be restabilized. While Christians are susceptible to Jewish temptations, while they may even be "Judaizers," and while Jews may convert and become Christians, in Guibert's Memoirs, even the most debased, "heretical" Christians do not become Jews. Christian identity is here maintained as somehow essentially different from Jewishness.
Guibert also accomplishes the restabilization of Christian self through an erasure of Jewish communities. Despite the real dangers that Jewish individuals are shown to pose for Christians, Jewish communities are not represented in the Memoirs as powerful, conspiratorial political entities within Western Europe, or even as having real force or presence in Guibert's world. Describing the attacks on Jews that accompanied the First Crusade, Guibert shows Christian power to be overwhelming, easily containing and eliminating Jews (II.5; 135).7 Though he (rather equivocally) disapproves of this violence, in depicting it he nonetheless asserts a Western European Christian hegemony that exists despite the presence of Jews in its midst and that is consolidated in the very movement to suppress or eliminate that presence.
We might expect, in moving to this "other" more distant than the Jews of northern France, that Guibert's sense of physical threat and revulsion would also become more distant, less distinct. But this is not the case. Perhaps it is because Islam is so distant, evoking a different sort of anxiety than more proximate "others," that it and its supposed physical debasements can be described in quite full detail. While the refusal to represent Judaism in the Memoirs is one strategy for projecting a "beyond" to Christian identity, the vivid representation of Islam in the Gesta is another, if opposed, strategy to accomplish a similar end. With the distinction between the Christian and the Muslim secured by distance, Islam can be brought into clear focus to represent what is to be ruled out of a communal Western European identity.
The movement here, however, is not unambivalent. While distance may allow Islam to be represented more fully than Judaism, that full representation in turn makes for an intensification of the sense of Islamic threat. The "other" here is conceived not, like the Jews of the Memoirs, as a scattered presence within a Christian hegemony, but as a massive and uncontained hegemony of its own.9
A vast, "nefarious institution," Islam threatens to breach the boundaries that secure its distance, and Guibert moves, at the same time that he represents the Islamic "other," to recontain it. In part he accomplishes this through a displacement of attention from the current moment to a moment of origin and from the whole of Islam to a single human being, Muhammad.10 Identifying the religion with its founder, and particularly with his diseased, fragmented corporeality, Guibert contains the "otherness" of Islam in a single, frail and frangible, body.
In this account, Muhammad is clearly identified with (hetero)sexual desire and a strong materialism. He suffers from epilepsy, a debility Guibert associates with sexual activity.11 Islam, however, depicts this disease not as the bodily debasement that, in Guibert's view, it is, but as a spiritual gift.12 The deception here is one that, in Guibert, becomes quite generally emblematic of Islamic ideology: "filthy and contemptible" matters, bodily degenerations, masquerade as holy, spiritual experience. Where the central Christian mystery is a divine taking on of body that leads ultimately through the corporeal abasement of the crucifixion to the rebirth and apotheosis of dead flesh, Guibert's account shows Muhammad's body only illegitimately claiming spiritual power. Indeed, the prophet's physical infirmity is fulfilled in a death made to contrast starkly with the miraculous overcoming of death at the heart of Christian revelation.13 Muhammad falls into an epileptic seizure, is discovered by a herd of pigs, who eat and "dismember" him so fully that only his "ankle-bones" remain. Guibert comments:
But if the things [claimed by] the sect of the Manichees concerning purgation are true--that in everything eaten a certain part remains profane to God; and that the same part may be purged for God by the chewing of the teeth and the stomach's digestion, and that the purged part may now be converted into angels, who may be said to come from the belchings and windiness expelled from us--should we believe that the sows fed on the flesh of this man produced angels and sent them forth from here to there in their great farts? . . . They add that he was assumed into heaven, and [his] ankle-bones alone left behind as a monument for his faithful, which [bones] they still revisit with infinite veneration.14Here, as in the transformation of Muhammad's epilepsy into divine visitation, the bodily debasement of Islam is falsely referred to a spiritual realm when, in Guibert's view, the only true metamorphosis Muhammad can be said to have undergone is from living flesh to "flatus" and to those dead bodily "vestigia" that con- tinue to lead his followers astray.
While Guibert thus attempts to deny Islamic claims to spiritual "truth" and temporal power, the containment or neutralization of Islam in the Gesta is never complete. At every point, even in the temporally distanced account of Muhammad, the Muslim "other" is felt somehow to touch on Christianity, and particularly in corporeal ways. The degeneracy of Muhammad's body, illegitimately claiming its own transcendence, corresponds to the larger body of Islam that illegitimately, and violently, seeks in the current moment to displace Christianity. Christian churches are made into mosques;15 faithful Christians, both women and men, are raped; a bishop is killed "by means of sodomitical abuse."16
The attack of Islam on Christianity here is much more violent and concerted than the Jewish seduction of Christians in Guibert's Memoirs: the whole of Christianity is at risk. And where the "Judaizers" of the Memoirs choose to behave as they do, here Christianity is positioned as victim of Islam's powerful "perversions." But Guibert also moves to present (Greek) Christianity as not simply a victim. The Eastern church, the spawning ground of "heresies," is in Guibert's view susceptible to Muslim attack because in many ways it is itself already "perversely" like Islam: Guibert notes, for instance, that the Greek Emperor has ordered each family to prostitute one of its daughters and to castrate one of its sons.17 As the home of such corrupt practices, is it any wonder that Eastern Christianity is both subject to foreign corruption and in need of the virile, desexualized knights of France who, in their pursuit of the Crusade, "thought [their] most beautiful wives mean, as though something decaying," rejecting "the sight of tokens of the promiscuous sex, once more pleasing [to them] than any gem"?18 As Guibert's text shows the subjection of Christian body to Muslim physical violence, it also shows the possible implication of a (debased, Eastern) Christianity in an economy of body like the Muslim. While in one sense all of this serves to confirm the purity of Latin, Western Christianity over against its "others," the distinction between Western Christian and "other" is undermined via the middle term of Greek Christianity.
Christian attacks on the body of the "other" are especially vexed, given the ways in which Christian theology, history, and ritual are themselves embedded in embodiment. As medieval Jews involved in polemical debate with Christians quickly learned, the Christianity that attacked Judaism based on its excessive physicality was itself vulnerable to similar attack. Listen to Joseph Kimh.i on the Christian incarnation:
[H]ow shall I believe that th[e] great inaccessible Deus absconditus needlessly entered the womb of a woman, the filthy, foul bowels of a female, compelling the living God to be born of a woman, a child without knowledge or understanding, senseless, unable to distinguish between his right hand and his left, defecating and urinating, sucking his mother's breasts from hunger and thirst. (36-37)The attack on Jewish or Muslim body, so easily available and so attractive to a writer like Guibert, necessarily had its risks when spoken out of a religion that made body so central to its own theology.20 When Guibert comes to write a treatise against the Jews and Jean of Soissons, he writes "de incarnatione," defending body as the appropriate locus for Jesus's divinity. Quoting a Jewish attack on the incarnation much like Kimh.i's,21 he goes on to refute this position, arguing that God made all creatures good (col. 492) and that bodies, in the absence of sin, are "sancta."22 Guibert is tempted by, but tries to resist, the impulse to respond to attacks on the theology of the Incarnation with his own arsenal of anti-corporeal rhetoric:
Ask, most stinking and worthless one, concerning our Lord, if he spit, if he wiped his nose, if he drew phlegm from his eyes or ears with his fingers, and understand why he did things as the above with such respectability, and accomplished as well the remainder [of bodily functions]. . . . I tremble violently while I dispute such things; but you, sons of the devil, force me to it. . . . In short, accept that God humbly took on all human things and feared nothing human except sins.23
Guibert here feels but squelches the impulse to attack the "stinking" and "worthless" body of the "other" who would wrongly read Christ's association with spit and snot and phlegm as a debasement of his body; such a visceral attack on Jewish disbelief must be cut short because Guibert's project here is to mount a general defense of human body in the context of Christ's incarnation. This "body-positive" view stands in strong contrast to the deep revulsion at bodies that, in the Memoirs and Gesta, adheres especially to Jewish and Muslim bodies, but in the De pignoribus sanctorum and elsewhere also clings to the bodies of Christians and the (supposed) bodily remains of the saints. While, in a certain theological context, an anti-Jewish or anti-Muslim position might demand the defense of human body, elsewhere it might evoke a violent attack on the physically embodied. This incoherence presents a central problem not only in Guibert's writing but in medieval anti-Semitic literature more generally. It ultimately reflects a deep ambivalence within Christianity about the viscerally-powerful and disturbing embodiments at the heart of the Christian mystery itself, an ambivalence worked out not only through Christians' own bodily celebrations and asceticisms but also upon others' bodies in acts of violence that must be written back into our understanding of Christianity's self- constructions if we are not merely to embrace the sanitized histories that those self-constructions so often project.