Green Knight of the story turns him green. He tests Moses three times by doing seemingly evil acts, which are eventually revealed to be noble deeds to prevent greater evils or reveal great goods. Both the Arthurian Green Knight and Al-Khidr serve as teachers to holy and upright men (Gawain/Moses), who thrice tested their faith and obedience. It has been suggested that the character of the Green Knight may be a literary descendant of Al-Khidr, brought to Europe with the Crusaders and blended with Celtic and Arthurian imagery. The beheading game appears in a number of tales, the earliest being the Middle
Isles of Scilly land of Lyonesse, referred to in Arthurian literature, of which Tristan is said to have been a prince. This may be a folk memory of inundated lands, but this legend is also common among the Brythonic peoples; the legend of Ys is a parallel and cognate legend in Brittany as is that of in Wales. Scilly has been identified as the place of exile of two heretical 4th century bishops, Instantius and Tiberianus, who were followers of Priscillian. In 995, Olaf Tryggvason became King Olaf I of Norway. Born 960, Olaf had raided various European cities and fought in several