"Truly, I say to you, I will not drink again of the fruit of the vine until that day when I drink it new in the kingdom of God." (Mark 14:25).
Well, here we encounter the eschatological import of the Supper. What Jesus does in this Last Supper is institute something which grabs hold of the past (what He is preparing to affect on Calvary) and yanks it into the present in order to give to His own the promise and guarantee of a future. The day when I drink it new in the kingdom of God points to the resurrection and beyond.
In a way, this verse is sort of parallel to Paul's words in 1 Corinthians 11:25, "For as often as you eat this bread and drink the cup, you proclaim the Lord's death till he comes." Present eating and drinking that proclaim the past death of the Lord and all that He won by that death, until a future moment when He appairs in glory, and the foretaste of the feast is over (that would be the Eucharist) and the feast itself begins (that would be eternal life) the joyous homecoming party of God's people.
Pr. Will Weedon
