Read Matt 26.26-29. How can He drink it with us anew in His Father's kingdom if He is not resurrected? And that is part of what we celebrate in the Lord's Supper.
And where have I ever said He is not resurrected? He is the firstborn among many brethren. What I have said is that He does not instruct us to celebrate His resurrection.
But His presenting of the wave sheaf was His entry into heaven having risen from the dead so that He could present what He had accomplished before the Father. Had He not risen He could not have done so.
Exactly, He arose from the dead Sabbath afternoon. When the women came to the tomb, He was already resurrected...
Joh 20:1 Now the first day of the week Mary Magdalene went to the tomb early,
while it was still dark, and saw that the stone had been taken away from the tomb.
Joh 20:2 Then she ran and came to Simon Peter, and to the other disciple, whom Jesus loved, and said to them, "They have taken away the Lord out of the tomb, and we do not know where they have laid Him."
Notice that it is still dark and the tomb is empty?
Now we read on...
Joh 20:17 Jesus said to her, "Do not cling to Me, for I have not yet ascended to My Father; but go to My brethren and say to them, 'I am ascending to My Father and your Father, and to My God and your God.' "
He had not yet fulfilled the Wave Sheaf offering.
Now later that same day we read...
Joh 20:19 Then, the same day at evening, being the first day of the week, when the doors were shut where the disciples were assembled, for fear of the Jews, Jesus came and stood in the midst, and said to them, "Peace be with you."
Joh 20:27 Then He said to Thomas, "Reach your finger here, and look at My hands; and reach your hand here, and put it into My side. Do not be unbelieving, but believing."
He had been to the Father, presented Himself as our sacrifice and then returned.
You can stay on the cross. I will enjoy the resurrection
Although in fact there is no command in the new testament to observe the presenting of the wave sheaf. that is just your assumption. But we are to celebrate the fact that we will be with Him in His Father's kingdom as a consequence of His resurrection.
You may celebrate any man made tradition you wish, I will celebrate the Feasts of God.