The Reformers were wrong: the Mass is a true sacrifice

[T]here’s one doctrine in particular in which we see all (or almost all) of the Protestant Reformers arrayed on one side, and all of the early Christians on the other: the question of whether or not the Mass is a sacrifice. … 

This rejection of the sacrifice of the Mass continues among Protestants today [and] puts Protestants at odds with the whole of pre-Reformation Christianity, a fact the Reformers readily admitted. Martin Luther explains that the Church “universally believed” [that the Mass is a sacrifice] for good reason, since it agrees with the witness of the early Christians and the liturgical text itself…

To accept the Protestant argument is to believe that the whole Church, from the time of the early Christian martyrs onward, was deceived by Satan when it thought it was offering sacrificial worship to God.

On what basis do the Reformers justify such a radical stance? Luther argues that “there is nothing about a work or sacrifice” in the “plain meaning” of Christ’s words and deeds. … [Swiss Reformer Ulrich] Zwingli offers a stronger argument: …the Mass cannot be a sacrifice, because “Christ has sacrificed himself once and for all eternity as a true and sufficient sacrifice for the sin of all believers.”

The answer to Luther’s and Zwingli’s objection requires understanding Jewish sacrificial meals. Certain sacrifices required those offering the sacrifice to eat of it. … The killing and the eating of the animal were two dimensions to one sacrifice, not two distinct sacrifices.

We can see this perhaps most clearly with the Passover sacrifice. The Passover liturgy consisted of two aspects: the slaying of the lamb on 14 Nisan (Preparation Day) and the eating of the lamb at the Passover meal on 15 Nisan (Exod. 12:6, 8). Preparation Day prefigures Good Friday, a connection St. John makes explicit in John 9:14. This is the once-for-all sacrifice of which Hebrews 7 speaks. But if “Christ, our paschal lamb has been sacrificed” (1 Cor. 5:7), when and how do we participate in that sacrificial meal?

As St. Luke says, “the day of Unleavened Bread, on which the Passover lamb had to be sacrificed” (Luke 22:7), is Holy Thursday, at the Last Supper. But even though John describes Preparation Day as a sacrifice, and Luke describes the Passover meal as a sacrifice, these aren’t two separate sacrifices: they’re two aspects of the same Passover sacrifice. …

[E]ating the Passover lamp didn’t “re-sacrifice” the lamb slain on Preparation Day. It was rather the way in which a believer participated in the sacrifice and applied it to himself. [And] so when Jesus says at his Passover, “Do this in remembrance of me” (Luke 22:19), he’s not telling them to crucify him repeatedly, but telling them to repeatedly participate in the sacrificial meal.