Reading and hearing prophecy in the thirteenth century

The sixth book of Wolfdietrich D contains the hero's battle with the knife-throwing heathen king Belian. The scene I've always been most fascinated by, however, is the confrontation between Wolfdietrich and the king's daughter Marpaly. The hero is an unwilling guest in Belian's castle, but has not yet revealed his name to his host - which is good, since Belian knows that the only person who can defeat him in battle is someone from Greece named Wolfdietrich. Belian has consigned Wolfdietrich to Marpaly's bedchamber, where he expects the hero to end up like all the others whom his daughter rejects; their heads line the castle wall the next morning. But things get off to a better start this time, as Wolfdietrich and Marpaly are somewhat inclined to pursue a more permanent relationship; the one catch for Wolfdietrich is that he refuses to entertain the prospect of marriage to a non-Christian. As for Marpaly, she knows exactly who she is destined for. She says to Wolfdietrich,

 "I tell you indeed, I have preserved my virginity for fifty years for the sake of a worthy prince born in Greece whose name is Wolfdietrich. I have chosen him as my lord above all others."

"Beautiful woman, how do you know his name? Please tell me; it's no shame to you to do so. Has he already been born? You can tell me that."

Then the heathen woman retrieved a book. She quickly read the page where she found the name. "Yes, the bold knight has already been born," she said. "As I find it written here, the praiseworthy prince is thirty years, twelve weeks, and two days old. I'm not deceiving you - my family has owned this book of the old Sibyl for many years. A wise man wrote it from the prophetess herself. The praiseworthy prince has long since been born. I have kept the book for fifty years now. It tells of the prince, I tell you indeed, and how he will suffer in his youth but bear a crown above all other kings in his manhood."

 Even though we're clearly in the realm of the fantastic, this is a nice example of re-oralizing a written prophecy that is in turn a transcription of an originally verbal oracle. The media shifts do not lessen its force, nor does excerpting one prediction from a longer source. Marpaly and even Wolfdietrich express no doubt about the prophecy's validity, leaving Wolfdietrich to appeal to the Virgin Mary for aid and then to make the sign of the cross against Marpaly's magic. Wolfdietrich becomes Marpaly's master in a non-marital sense only after he kills her father Belian; Marpaly blinds Wolfdietrich with a magic fog, but Wolfdietrich finds one of her father's daggers and casts it at Marpaly, killing her. Reinterpreting a prophecy is usually not such a bloody matter.