"Tt" would have to be something that was not "finished since the beginning of time", but something that was just finished. He had just accepted some sour wine.
It was the completion of the Passover Seder.
This sounds suspiciously like Hauhn's book to me . I do not care for him because he seems makes up theology as he goes along.
Mar 14:24 And he said unto them, This is my blood of the new testament, which is shed for many.
Mar 14:25 Verily I say unto you, I will drink no more of the fruit of the vine, until that day that I drink it new in the kingdom of God.
He was not dead, He was not in the kingdom when he "drank" the vinegar off the sponge....not a cup
Mat 26:29 But I say unto you, I will not drink henceforth of this fruit of the vine, until that day when I drink it new with you in my Father's kingdom.
They were not in the Kingdom and He did not drink it from a cup with them
Luk 22:18 For I say unto you, I will not drink of the fruit of the vine, until the kingdom of God shall come.