Elijah, Where are You?

The Legend of Elijah

The Jewish people have a custom to leave a vacant seat and a place set at the Passover table for the Prophet Elijah. With the sound of a knock, the children run to the door and say, “Elijah, is that you?” When he comes, they expect him to be a herald of the coming of the Messiah, to resolve all unanswered questions concerning the Law of Moses, and to deliver God’s people into that Land promised by God to Abraham, Isaac and Jacob and to their offspring. This includes all twelve tribes of the House of Israel.

The Arthurian Legend

Similarly, in the Arthurian Legend of the Round Table, there is an empty seat awaiting the rightful king, being the Messiah, the Branch of David, aka King Arthur. He, in pulling the sword from the stone, will thus become the High King over all the House of Israel (Gen 49:8-10). This legend is tied to the story of the Holy Grail, the Last Supper and Joseph of Arimathea, who founded Glastonbury in Britain after the death of Christ.
But how are two Legends tied together?

Elijah - the rightful heir to the throne
The Sword in the Stone