Where Does the Structure of the Mass Come From?
There are a few ways to explore this. One could work through the entire history of the Mass’s taking shape. But there is also a more elemental and ancient answer to this question.
It begins, actually, with Moses.
Leading the Israelites through the Egyptian desert, Moses arrived at Mount Sinai. It was Moses alone who climbed the mountain to encounter God. This was not only about receiving the Ten Commandments. This was also when, through him, the Israelites entered into a “covenant” with God. A “covenant,” put simply, is when two parties who are not family, become family and treat each other as family. A marriage, for instance, is a covenant.1
There are several moments where God enters into covenants with the Israelites, and each covenant comes with instructions about how the family should treat each other. This is why, upon the mountain, Moses received not just the Ten Commandments, but a whole legal code for Israelite life ― how to manage one’s property, etc. These are family rules. By following God’s code, the Israelites participate in God’s family.
And God? How will God treat the Israelites now that they’re family? It’s just here where we see something that should remind us of the Mass.
By way of this covenant, God promised the Israelites two things. “If you will … keep my covenant,” he said, (1) “you shall be my own possession.” More than that, though, (2) “you shall be to me a kingdom of priests” (Ex 19:5-6).
Priests, of course, facilitate worship and sacrifice. And so, when Moses returned to the Israelites from up the mountain, he set about facilitating this covenant ― facilitating the marriage ceremony ― through an act of worship.
The text says he “built an altar at the foot of the mountain” and gathered the Israelites around him (Ex 19:4). It is precisely the primordial act of worship Moses here performs that gives us the structure for the contemporary Mass.
First, having written it down (Ex 19:4), Moses read aloud the legal code God offered upon the mountain. “He took the book of the covenant and read it in the hearing of the people” (Ex 24:7).
He then offered a sacrifice and sprinkled the blood among the people. He said to them, “behold the blood of the covenant which the Lord has made with you” (Ex 24:8). This might seem strange. But the Israelites were becoming one family with God. This was an ancient way of saying God and the Israelites were of the same blood.
Finally, Moses facilitated a meal. They ate the cooked and sacrificed animals. They communed not just with each other, but also with God. “They beheld God, and ate and drank” (Ex 24:11).
The structure of this ritual is exactly like the Catholic Mass.2
At Mass, God’s Word ― the “book of the covenant” ― is read “in the hearing of the people.” Then a sacrifice occurs ― Jesus’s sacrifice, re-presented by way of the Eucharist. There is even blood. Not, this time, the blood of sacrificed animals, but the blood of the sacrificed Jesus. Priests at Mass repeat Jesus’s words: “This is the chalice of my blood, the blood of the new and eternal covenant.” These are almost exactly the words of Moses: “Behold the blood of the covenant which the Lord has made with you.” Lastly, of course, the Mass is a meal: receiving the Eucharist. The sacrifice, like Moses’s sacrifice, is consumed.
Moses’s ritual at the foot of Mount Sinai marked the covenant between God and the Israelites. The Mass also marks a covenant ― in Jesus’s words, a “new and everlasting covenant.” And so the Mass has the same structure as that ritual which first recognized Israel as “a nation of priests.” The Mass is, indeed, a covenant-making ceremony. It constitutes our familial relationship with God. The Mass is a marriage ceremony, a ceremony that facilitates, underscores, and even constitutes our intimacy with God.
This nifty way of talking about it I learned from John Bergsma, Bible Basics for Catholics (Notre Dame, IN: Ave Maria Press, 2015), 3-5 and 61-83.
See Lucien Deiss, The Mass, trans. Lucien Deiss and Michael S. Driscoll (Collegeville, MN: The Liturgical Press, 1989), 33.