While it is true that the Mass is indeed a sacrifice--we do call the Mass "the Holy Sacrifice of the Mass"--it is not correct to say that we re-crucify our Lord.
Jesus does not suffer and die again at every Catholic Mass.
Rather, it is simply a re-presentation of the One Time Event that occurred 2000 years ago. It is the most sacred and important event that ever occurred in the history of creation, and we are privileged to participate in this at each and every Mass.
As Fr. John O' Brien wrote in his book, The Faith of Millions, "The Mass is the renewal and perpetuation of the sacrifice of the cross in the sense that it offers [Jesus] anew to God . . . and thus commemorates the sacrifice of the cross, reenacts it symbolically and mystically, and applies the fruits of Christ’s death upon the cross to individual human souls. All the efficacy of the Mass is derived, therefore, from the sacrifice of Calvary" .
And as Fr. Vincent Serpa says, "The Mass is the moment of His death brought into our lives in a concrete and physical way.:
Many Protestants bristle at this though of the Mass being a sacrifice. This event occurred 2000 years ago and, in their eyes, there is no way for us to participate in this event.
Yet, there is a glaring inconsistency in their position. For do not some of these Protestants profess that they are "washed in the Blood of the Lamb"? It appears that they, too, are participating in (and receiving benefits from) an event that occurred 2000 years ago.