Throughout the Old Testament the Jewish high priests were told by God to offer sacrifices of lambs, goats and bullocks as an atonement for sin: Then shall he kill the goat of the sin offering. (Leviticus 16:15) But these sacrifices did not actually achieve anything because: it is not possible that the blood of bulls and of goats should take away sins. (Hebrews 10:4) These sacrifices were merely a symbol of the true sacrifice of Jesus Christ which was to come. As John the Baptist says of Christ: Behold the Lamb of God, which taketh away the sin of the world. (John 1:29) The Old Testament itself, also prophesied that one day a man, rather than a bull or goat, must be the sacrifice for sin: thou shalt make his soul an offering for sin. (Isaiah 53:10)
The importance of the cross of Christ to Christianity, is shown not only by the Old Testament sacrifices foreshadowing it, but also by the institution by the Lord Jesus, of the breaking of bread which recalls it: the Lord Jesus the same night in which he was betrayed took bread: And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me. After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as you drink it, in remembrance of me. (1 Corinthians 11:23-25)
When Jesus says, ‘This is My body’, he means only that the breaking of the bread represents His body. If someone shows a photograph of himself when he was young and says, ‘This is Me when I was younger’, the listener understands that the words ‘this is’ mean ‘this represents’. No one believes that the person speaking used to be made out of photographic paper, but was later transformed into flesh and blood. The Roman Catholic doctrine of transubstantiation is equally ridiculous. Jesus Christ is in heaven until He returns to reign. The idea that He turns Himself into bread and wine and comes down to earth is abhorrent. Believing that God is in a piece of bread is as much idolatry as believing God is in a piece of stone.
The Roman Catholic doctrine also denies the finished work of Christ, by falsely teaching that Christ must be repeatedly offered, contrary to the teaching of Hebrews 9:25-28: Nor yet that he should offer himself often, as the high priest entereth into the holy place every year with blood of others; For then must he often have suffered since the foundation of the world: but now once in the end of the world, hath he has appeared to put away sin by the sacrifice of himself.
So the bread and the wine are purely symbolic. As Jesus tells us to partake in remembrance of Him, the bread and the wine are solely to help us remember the work of the cross. Breaking is a destructive process and the breaking of the bread symbolises the destructive sufferings Christ endured in His body upon the cross. Shedding of blood is symbolic of and proof of death; and the cup of wine, which represents Christ's blood, symbolises the giving of His life in death.