The reason Jesus comes to feed us his body and blood is to keep us in Him, to take what is ours and to give us what is His.  He comes to give us the very wedding garment we need to stand in the judgment.  The Holy One of God comes to give you His holiness. 

This Sacrament reaches back into the past .  It also reaches into the future by virtue of its contact with the eternal High Priest (Hebrews 6:2).  The Lord's Supper reaches over the span of nearly twenty centuries between Jesus' crucifixion and today by feeding us the body given into death and the blood shed on Calvary.  It also reaches over the span of time from today to the Last Day, for the Judge of that day stands in our midst now.  He comes for us to make a blessed exchange.

(The Blessings of Weekly Communion - pp. 211, 212). 

For as often as you eat this bread and drink this cup, you proclaim the Lord's death till He comes. (1 Corinthians 11:26).