The celebrant of the mass is Christ. The Priest acts in persona Christi - in the person of Christ. This capacity is recorded in the scriptures: check 2 Corinthians 2:10 in either the King James or the Douay-Rheims bibles and see where Paul forgave the sins of others in the Person of Christ. To bless and break the bread is a command; “Do this, as often as you do it” entering into the Sacrifice as a remembrance in the Jewish tradition - not merely symbolism.
The mass is a re-presentation of the sacrifice on Calvary - making that sacrifice present to us in a non-bloody manner. Catholics and Orthodox do not “re-sacrifice” Christ. First, that is impossible. Second, He did not command it. Yet, when He instituted the “New Testament” in the upper room, He specifically used sacrificial language.
Here is something that few Christians seem to know: the book that the world knows as the New Testament is called that solely because Christ referred to the institution of the Holy Eucharist as the “New Testament.” Te Apostles and disciples gathered on the Lord’s day to celebrate the Holy Eucharist - Paul writes very clearly about this in 1 Corinthians.
Since the radical re-invention of the faith in 16th century Europe, all of this has passed away. Yet, Christ taught no such thing as worship “services”, as there is no worship of God without sacrifice. Christ never taught bible alone - or bible anything, as far as that goes. In fact, Christ never taught any of the uniquely Protestant beliefs or actions. Not a single one.
Rather, Christ sent Apostles (“He who hears you hears Me” - Luke 10:16) accompanied by the Holy Spirit. You might read the oldest known “catechism” of the early, apostolic Church, the Didache. In it is instructions for those in the early Church. Kindly note there is not a single peep about writing or scripture of any kind.
In that Didache you will find the origins of the nascent Church. Yet, the scriptures are added to it, a win-win. We are constantly amazed at the faith of our separated Protestant brothers, and the good that they do. Yet, when we gather with them, whatever activity they enter into feels decidedly empty. I hope that you will understand why.
The mass, the Holy Eucharist - Christ Sacramentally present to us - is the source and summit of the Christian faith. The bible is not.