Wolfram von Eschenbach

Fideler, David R. "The path toward the Grail The Hermetic sources and structure of Wolfram von Eschenbach s Parzival." In ALEXANDRIA Cosmology, Philosophy, Myth, and Culture. 1 ed. Phanes Press. 

During the Middle Ages, as alchemy began to spread through Christian Europe, the Philosopher s Stone came to be equated with the Holy Grail and Christ himself. Wolfram von Eschenbach, in his Arthurian epic Parzival, describes the Grail not as a cup or chalice, as is traditional, but as a stone beyond price, the stone which the builders rejected, but which has become the corner stone . 

David R. Fideler, "The Path Toward the Grail The Hermetic Sources and Structure of Wolfram von Eschenbach s Paizival, in Alexandria The Journal of the Western Cosmological Traditions 1 (Grand Rapids Phanes Press, 1991), pp. 187-227. 

Wolfram von Eschenbach, Parzival Jorg Wickram, Der Knabenspiegel... 

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