After Abram [later to be named “Abraham”] defeated the forces of King Chedorlaomer, “Melchizedek, king of Salem, brought out bread and wine. He was a priest of God Most High. He blessed Abram with these words: ‘Blessed be Abram by God Most High, / the creator of heaven and earth; / And blessed be God Most High, / who has delivered your enemies into your hand!’ And Abram gave him a tenth of everything” (Gn 14:18-20). Like other kings of this time, Melchizedek carried out priestly functions. Here, as in Psalm 76:3, Scripture identifies “Salem” with “Jerusalem.”
Psalm 110 begins, “The Lord says to my lord.” In Matthew 22:41-45, Jesus tells us the psalmist is David, and that he is addressing the Messiah when he sings, “You are a priest forever in the manner of Melchizedek” (Ps 110:4). The end of that verse can also be translated as “because of the word of Melchizedek.” Hebrews 7:17 addresses the words “you are a priest forever according to the order of Melchizedek” to Our Lord as the divine high priest.
The first Eucharistic prayer calls a roll of notable offerings — those of Abel, of Abraham and of Melchizedek — as prefigurings of the redemptive sacrifice offered by the divine Son of God.