This is the classic Reformist view of the Lord’s Supper - a purely symbolic re-enactment that reminds us of what Jesus did on the Cross.
Which is all we need if we are simply doing it “in remembrance of” Him and His once-for-all sacrifice. He did not tell us the Lord’s Supper was instituted for any other purpose. We remember what He did for us. We don’t put him back on the Cross to suffer and die again. That was once-for-all. Done. But we need to remember it. The Lord’s Supper serves that purpose.
Catholics believe that the Eucharist is not just a symbol but is an actual participation in the one sacrifice. To use modern terminology, the Mass is a point in space-time that makes it possible for all people to stand at the foot of the Cross and sit in the Upper Room.
When the Gospel is preached to make disciples (Matt. 28:19), the message of the Cross is given and people are told He died for their sins, which He bore on the Cross. In a sense their sins, our sins, put Him on the Cross. That message puts people “at the foot of the Cross” with a decision to make—accept what He did as applying to their sins, or walk away and have no part of it. That one sacrifice either is made personal or it is rejected as no sacrifice at all. To that extent only does anyone “participate” in the one sacrifice. Christ Himself does not go back on the Cross for anyone, except as sinners see it in the preaching of the Gospel. They see the once-for-all sacrifice when they are told about it. And after they accept it, if they do, they are reminded of it every time they take the Lord’s Supper.
No, the whole point of Hebrews is that the sacrifices of the Old Covenant have been fulfilled in the Sacrifice of the New Covenant. The daily sacrifices of the Temple are no longer needed because the Perpetual Sacrifice has been offered. We have a High Priest who is also the Lamb. Our earthly priests represent Him offering Himself to the Father.
No, there is no provision in Hebrews for earthly priests to “represent Him offering Himself to the Father.” None whatsoever. There was ONE, ONCE-FOR-ALL sacrifice by Christ and HE offered it Himself ONCE-FOR-ALL. One sacrifice and one offering. Both completed, never to be repeated, just remembered.
Hebrews 9:
24. For Christ did not enter into a sanctuary made by hands, a copy of the true one, but heaven itself, that he might now appear before God on our behalf.
25.
Not that he might offer himself repeatedly, as the high priest enters each year into the sanctuary with blood that is not his own;
26. if that were so, he would have had to suffer repeatedly from the foundation of the world. But
now once for all he has appeared at the end of the ages to take away sin by his sacrifice.
27. Just as it is appointed that human beings die once, and after this the judgment,
28. so also
Christ, offered once to take away the sins of many, will appear a second time, not to take away sin but to bring salvation to those who eagerly await him.
Hebrews 10:
10. …we have been consecrated through
the offering of the body of Jesus Christ
once for all.
11. Every priest stands daily at his ministry, offering frequently those same sacrifices that can never take away sins.
12. But
this one offered one sacrifice for sins, and took his seat forever at the right hand of God;
13. now he waits until his enemies are made his footstool.
14. For
by one offering he has made perfect forever those who are being consecrated.
The Heavenly sanctuary is the focus here - both in Hebrews and in Pope John Paul’s book and in the Mass. The once-for-all sacrifice of Calvary is offered perpetually and eternally on the altar in Heaven (see Revelation - the Lion of Judah is the Lamb sacrficed from the foundation of the earth.) When we go to Mass, we participate in the eternal Heavenly liturgy. One of the requirements of the Passover was that everyone consumed the flesh of the Paschal sacrifice. In the Eucharist Jesus made it possible for us to consume the sacrifice of His flesh, that commandment He had given (John 6) that was so disconcerting that many of His followers abandoned Him.
No, the once-for-all sacrifice of Calvary was offered once-for-all, not “is offered perpetually” in the present tense, as was the error of the Pope in changing the tense from past tense to present tense. Christ entered the heavenly sanctuary once-for-all and offered His one sacrifice once-for-all and has thereby obtained eternal redemption for us.