The Holy Grail is a story that most people are familiar with. From the mythical chase of Arthur and his Knights of the Round Table to the archaeological exploits detailed in Indiana Jones and the Last Crusade and The DaVinci Code the story of the Holy Grail is a common culture myth. The cup, which was supposed to have caught the sweat and blood of Jesus Christ at the crucifixion and which he had drunk from during the last supper supposedly became a holy relic with powers that include the gift of immortality. While this is a compelling story, that's really all it is... a story.
Have you ever wondered What Angels Really Look Like (According to The Bible)?
Also, did you know that "Thou Shalt Not Suffer A Witch To Live" Is A Translation Error?
But It's In The Bible!
... Isn't It?
If you flipped through your copy of the Bible and looked for mention of the Holy Grail (as I'm very sure you just did) you would find that Jesus Christ did drink from a cup at the Last Supper. Just like everyone else at the table did. That is the only mention of the grail as far as the Bible is concerned, though. It was no more important than any other item found at the table.
As if that wasn't disheartening enough though the story about Joseph of Arimathea collecting the blood and sweat of Jesus Christ is not mentioned anywhere in biblical script. This little addition isn't even biblical; it was created by author Robert de Boron in his book about Joseph of Arimathea, who is supposed to have taken the grail to Britain after using it to survive his own death.
Robert de Boron's fictional book.
But What About Arthur?
Well, What About Him?
Perhaps the most famous men to ever chase the grail were King Arthur and the Knights of the Round Table (excluding Harrison Ford and Sean Connery). They rode hither and yon, faced temptation and monsters, and in the end were victorious in finding this miraculous chalice!
Well, not quite.
Arthur and his knights did go on a quest for a great and powerful relic (because what else are kings and knights going to do?). The original quest of Arthur and his knights embarked on though was to find a magic cauldron; something much bigger and decidedly more Celtic than a grail. This change of macguffin was added by Chretien de Troyes, a French poet who decided to alter the telling of the Arthurian legend. This change was made before the alterations by Boron, who was likely basing his work off of the Frenchman's interpretation of the newly minted Grail Quest.
These are the two big changes made to historical literature that brought the Holy Grail into common Western culture. All further myths and legends up to and including the mysterious DaVinci Code and the idea that the mystical cup refers to the hidden bloodline descended from Jesus are all using these alternative documents as basis for their stories. Nowhwere in the actual Bible is the grail assigned the slightest importance, and as far as the source is concerned there is nothing special about the cup despite Jesus having once drunk from it. Just think about that next time you watch Monty Python's interpretation, and see if it makes the film any funnier.