What does past tense mean to God? What does “gone now” mean to God? You are using terms that only apply to us limited humans and mean nothing to God.
God is outside time and space. Calvary may be in the past for us but it is—in a sense—still present to His Eternity.
This is the mystical reality that the Holy Eucharist touches upon.
At the Mass Calvary is present again. Not that it *happens* again as a historical event, but that God in His ineffable Divinity opens up a portal, so to speak, to connect those of us in the pews at that moment to the Hill of Golgotha on that wondrous Good Friday.
By “bloodless” sacrifice we mean that there is no *new* shedding of blood. But of course, there was already a shedding of blood as Calvary as you correctly pointed out.
What the Mass does principally is unite the sacrifice at the modern altar with the sacrifice on the Cross. And that’s exactly what Christ said at the Last Supper—”This IS my body, this IS my blood”. It is a real and true sacrifice because of its connection to Calvary.
If Catholics think it’s real blood they put Christ, his apostles, and themselves in the position of breaking the law against eating blood. In that they put Jesus in the position of not being sinless.
Christ died within the confines of time and the Holy Spirit tells us that in heaven, Jesus is seated at the right hand of the Father.
The Catholic church claim that events on earth are being eternally played out in eternity has NO basis in Scripture and is absolutely contrary to the clear statements of Scripture that tell us exactly what Christ IS doing in heaven.
And it isn't eternally dying over and over again.
Talk about trampling the blood of Christ underfoot.
That is some much desperate special pleading, as it is not really applicable to the issue and would make any reference to beginnings and cessations meaningless.
For while it is true that God is outside time and space, we are dealing with His revelation which deals with us in time and space. In which He speaks of beginnings and culminations, including the creation of the universe and the work of atonement, while your hermeneutic here would make such parameters in revelation irrelevant.
The Holy Spirit repeatably states the atonement was a one time offering, but you make the Mass into an ongoing atonement, "a sacrifice of propitiation, by which God is appeased and rendered propitious," as by it He "offers himself a most acceptable Victim to the eternal Father, as he did upon the Cross," if you will be consistent with such RC teaching.
By “bloodless” sacrifice we mean that there is no *new* shedding of blood
But that Christ continues to offer it as an atonement, while Scripture states that was done and finished, and souls appropriate the benefits by effectual faith in the gospel of salvation, not be consuming physical food of any sort.
”This IS my body, this IS my blood”.
Which obviously, in the light of the rest of Scripture, did not mean Christ was in their stomach while He say before them, any more than David poured actual human blood out on the ground as an offering to the Lord, though he plainly stated,
And the three mighty men brake through the host of the Philistines, and drew water out of the well of Beth–lehem, that was by the gate, and took it, and brought it to David: nevertheless he would not drink thereof, but poured it out unto the Lord. And he said, Be it far from me, O Lord, that I should do this: is not this the blood of the men that went in jeopardy of their lives? therefore he would not drink it. These things did these three mighty men. (2 Samuel 23:16-17)