Melchizadech is the "priest unborn" asked for in the last riddle...he was a priest from "Salem" (later "Jerusalem") that met Abraham the Patriarch (read Genesis) to whom Abraham gave 1/10th of his wealth.   Abraham also "worshipped" this priest. Since there is no record of Melchizadech before or after this encounter, his presence is quite mysterious. He is known as the priest unborn.   Interesting Biblical stuff.