In Christian belief, the priesthood of the Order of Melchizedek is a line of priesthood that ends with the priest and king Jesus Christ. Because Jesus was not a descendant of Aaron, he did not qualify for priesthood under the Jewish law and therefore is considered a "priest forever in the order of Melchizedek."
The life of Melchizedek, a priest and the King of Salem, is outlined in Genesis in the Old Testament of the Bible. He is recorded giving the sacraments of bread and wine for the first time to Abraham. Jesus would later fulfill this prophecy in the New Testament with the last supper. It was prophesied in the Old Testament that the coming Saviour (Jesus) would be a priest forever in the order of Melchizedek.
The priesthood of the order of Melchizedek serves as the basis for priesthood in the Catholic Church with Catholic priests following the same traditions, including the breaking of bread and wine in remembrance of Jesus. Melchizedek also represents the first recorded instance in the Bible of a person holding the role of both King and High Priest. This foreshadows the role of Jesus in the New Testament, who holds both roles and is seated at the right hand of God. Some Christians conclude that Melchizedek is an earlier incarnation of Christ.