If a prediction made by a magician who was himself a myth strikes the present-day reader as suspect if not worthless, the medieval mind, preoccupied with sorcery and tales of chivalry and untroubled by the future scholarly detective work that would exhume the sources of the Arthurian legend, gave Merlin's presumed words credence, the Sibyl and the Bede joining him as remote mystical buttresses to the more precise predictions made around the time of Joan's birth. Once Joan had announced herself as the vehicle of God's salvation, her initial examiners turned to prophecy as a means of retroactively validating a declaration they desperately wanted to be true, and during the late Middle Ages, Merlin, the Sibyl, and the Bede were typically summoned as a trio, each associated with pronouncements at once mysterious and archetypal. "A virgin ascends the backs of the archers / and hides the floweer of her virginity," was Merlin's contribution. Copied from Geoffrey of Monmouth's twelfth-century History of the Kings of Britain, which introduced the Arthurian legend to continental Europe, it invited a broad spectrum of interpretations, as must any lasting prediction. Applied to Joan, it sanctioned her authority to lead men in war and underscored her celibacy, protected by male attire and armor. The Church, whose reflexive revisionism cannibalized any myth that might distract from its doctrine, had long ago consumed and rehabilitated the Sibyl, a legendary seer traced as far back as the fifth century BC and often referred to in the plural. Whether one or many, having left no recorded oracle, the Sibyl could be summoned to reinforce any appeal. The Venerable Bede's presentiment of Joan's saving France was harvested from an Anglo-Saxon poem written six centuries after Bede's death and rested on a single sentence: "Behold, battles resound, the maid carries banners."
Jesus's advent was similarly legitimized. The evangelists applied messianic prophecies as generic as "For unto us a child is born, unto us a son is given, and the government shall be upon his shoulder" to the coming of Christ and revised what they knew of Jesus's life to fit specific predictions made by the prophets Isaiah, Daniel, and Hosea. More significant, Jesus consistently presented himself as the fulfillment of Old Testament prophecy, for example, deliberately staging his Palm Sunday entrance to Jerusalem according to the six-hundred year-old direction of Zechariah. "Lo your king comes to you," the prophet wrote of the Messiah, "triumphant and victorious is he, humble and riding on an ass." This wasn't prophecy fulfilled so much as a public announcement resting on biblical scholarship, for Jesus was, if nothing else, a Jew who knew his Scripture, knew it as well as did the high priests who called for his death in response to the presumption of his claim of divinity. "All this has taken place," he said to his disciples, "that the Scriptures of the prophets might be fulfilled." He was, Jesus told the temple elders, the Messiah whom Isaiah promised would come to "set at liberty those who are oppressed."
Like Jesus, Joan recognized herself in Scripture, but from the New rather than the Old Testament. "I was sent for the consolation of the poor and destitute," she proclaimed, borrowing her lines from Gospel accounts of a career that, like hers, convinced by means of miracle, spectacle, and prophecy fulfilled.
Of the handful Joan would have heard growing up, the only prophecy she is known to have identified with her mission was particular to her place of birth: France was to be ruined by a woman and restored by a virgin from the marshes of Lorraine. As Old and New Testaments illustrate, prophecy has always been a political medium, broadcasts from a jealous god who distributes land grants to nations worthy of reward. In 1398, when France's national oracle, Marie Robine, foresaw the desolation of her homeland, she came directly to the court in Paris to describe it in full. A recluse of humble origins embraced by the poor and the exalted alike, Marie derived her authority from the attention popes paid her apocalyptic Book of Revelations. Refused an audience with Charles VI, who was likely in a state of mental confusion, the seer warned that "great sufferings" would arrive. One vision presented Marie with armor, which frightened her. "But she was told to fear nothing, and that it was not she who would have to wear this armor, but that a Maid who would come after her would wear it and deliver the kingdom of France from its enemies." While witnesses remembered Joan speaking only of the prophecy specific to Lorraine, she undoubtedly knew the content of Marie's visions. Not only were they common lore, but they illustrated her vocation and validated her wearing armor.