Why do we do that? Catholic Traditions Explained

One of my coworkers said that Catholics believe we kill Christ again when we celebrate the Mass since it is his sacrifice. I know that is not right, but how do we explain it?
We do indeed believe that the Mass is the unbloody sacrifice of Jesus on the cross and we believe that the sacrifice is made present again on the altar—not to repeat it, but to join ourselves to it. We are joined to the saving work of Christ, not just simply remembering it.

The closest thing we might have in our culture is when a couple saves some wedding cake in the freezer, and on their first anniversary they may watch their wedding video and eat the cake, all to recapture the moment. The Jews celebrate a Seder meal, not to remember the Passover, but to participate in it through the ritual foods, questions, and readings. The Catechism of the Catholic Church describes the Mass as the “Holy Sacrifice, because it makes present the one sacrifice of Christ” (#1330). To think that we must sacrifice Christ over and over again would negate what he did on Calvary. To celebrate and renew it each day allows us to participate in it. That is the “source and summit” of Christian life (#1324).
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