We encourage the reader to study this fascinating article by professor Daniel Scavone:
Joseph of Arimathea, the Holy Grail and the Edessa Icon
One may read more about this subject at:
Wilson’s landmark 1978 book [1979 The Shroud of Turin: Burial Cloth of Jesus? (Rev. ed.). Garden City NY: Image Books.] also reached into medieval romance literature recognizing a link between Byzantine rituals and Holy Grail legends. These stories began in the late 12th century right at the time when many western soldiers and fellow travelers were returning home after being exposed to the traditions and wonders of the Orthodox East. Grail stories were “…essentially about a dish or chalice of extreme holiness that forms the goal of a knightly quest.” The central point of some is “a very special secret vision of Christ” wherein a transformation of the vision occurs:
… the wafer of the host first changing into Christ as a child, then Christ as an adult, with, of course, the bleeding wounds (Wilson 1979: 162).
Other Grail readers, even some with no interest in the Turin Shroud, have endorsed thinly veiled Byzantine connections. Professor Daniel Scavone has delved more deeply into this Eastern Christian/Byzantine link. In a major paper he opines:
Specific documents and rituals surrounding the Mandylion resonate closely with and provide precise sources for the chief attributes of the Holy Grail. Like the legendary Holy Grail, this cloth was linked to Joseph of Arimathea, resided in a place known as Britium [another name for Abgar’s residence in Edessa], was thought to have contained Jesus’s body, captured Jesus’s dripping blood on Golgotha, and was displayed only rarely and in a gradual series of manifestations from Christ-child to crucified Jesus (Scavone 1999: 1).
Scavone has traced the sources of early western Grail literature back to apocryphal NT books like the Gospel of Nicodemus (about 4th cen.), the book known as I, Joseph (5th cen.) and various “Latin Abgar” descriptions of a polymorphic (changing) Jesus strongly associated with the Edessa Image. These were supplemented by elements from the newly learned Byzantine Greek Eucharist to provide the imagery and themes used in Holy Grail legends. Although tempting to equate the Holy Grail with the Shroud, Scavone does not do so, seeing the Grail stories as confused derivatives of the latter.