At the Last Supper Christ instituted the Eucharist as Catholics understand it

I would like to start by thanking SkepticsAskHere for a variety of interesting and well developed arguments. I'm glad to hear that my opponent went to a Catholic school since this should make our communication all of the easier. I will begin by considering my three contentions, followed by discussing the point brought up by my opponent. Contention 1: The Last Supper ---When we examine verse 28, I see two possible meanings. Either Jesus is referring to His crucifixion which is about to take place, or the contents of the cup. Remember that in the Old Testament that one of the main ways to atone for sins was a blood sacrifice. So did the contents of the cup forgive many sins, or did the blood sacrifice that Jesus took on the cross forgive many people?--- My opponent is correct to point out that Jesus seems to be referring to his crucifixion which is about to take place. After all, it was Christ's death which brought about the forgiveness of sins mentioned in verse 28. However, when we look at what preceded verse 28 we see that it says, "Then he took a cup, and when he had given thanks, he gave it to them, saying, "Drink from it, all of you. 28 This is my blood of the[b] covenant…" It is obvious that he is referring to the wine in his hands which he is telling them to drink when he says "this is my blood". The only way to reconcile these two facts is to accept the doctrine of the Eucharist which states that the very cup of wine which Christ holds is the very blood which he shall shed the next day for the forgiveness of sins. ---My opponent's logic supposes that if Jesus does not say that He is speaking symbolically, then we can't take him as such. Well if that's true then we must take the following verse quite literally.--- Yes, I am saying that we should believe what the bible says. If there is no compelling other reason why Christ would have said ‘this is my body', then we have to assume he meant exactly what he said. Contention 2: John 6 ---Well if we are to interpret these passages literally then there are several verses in which Christ condones cannibalism of His body. So the Roman Catholic view is a violation of Levitical law "For as for the life of all flesh, its blood is identified with its life. Therefore I said to the sons of Israel, You are not to eat the blood of any flesh, for the life of all flesh is its blood; whoever eats it shall be cut off," (Lev. 17:14).--- Firstly, I would like to point out that the ‘cannibalism' of the Eucharist as you have phrased it is far different from normal cannibalism. To destroy human flesh so it may be devoured is wrong and repulsive. Through the miracle of bread turned into flesh in the Eucharist, Catholics do not have to be cannibals to eat Christ's flesh, since they are eating him under the appearance of bread. Thus, passages like "unless you eat the flesh of the Son of Man and drink his blood, you have no life in you," do not condone cannibalism but foreshadow the miracle of the Eucharist. As for the Old Testament law that Jews were not to eat flesh, the Old Testament passage was obviously intended to apply to normal flesh with normal blood. Something as unique and miraculous as bread which is God would not fall under this ban. Thus Christ's body is exempt from this passage of Scripture just as Christ himself is exempt from the passage of St. Paul's saying, "As it is written: "There is no one righteous, not even one." (Romans 3:10) Finally, the fact that Jews were forbidden to have anything to do with eating blood goes to show that Christ was speaking literally. John 6:66 says, "From this time many of his disciples turned back and no longer followed him." I ask the question ‘why did his followers suddenly turn back?' The answer is found a few verses earlier where it says that the Jews were grumbling after Christ finishes saying, "whoever feeds on this bread will live forever." They are leaving because as Jews they abhor the thought that Christ would have them drink genuine blood and commit cannibalism. If this truly were a misunderstanding, then why did Christ not correct the mistake? His silence is louder than words. Contention 3: 1 Corinthians 11 My opponent did not really address this point for the sake of time, but I would appreciate it if he would devote at least a few sentences to it. Specifically, I am interested to know how he explains St. Paul's strong language in reference to the punishment for eating the bread and wine unworthily. "Whoever, therefore, eats the bread or drinks the cup of the Lord(AC) in an unworthy manner will be guilty concerning(AD) the body and blood of the Lord." He specifically says they will be guilty of Christ's body and blood. Now for my opponent's case: Contention 1: Jesus speaks of the Spirit I believe that there are four main points being made and I will break it up as such P1: Nowhere in Scripture is this teaching: To the contrary, all three of my Contentions point to the fact that Scripture does preach in numerous places to the fact that it is Christ's real body and blood. "For my flesh is real food and my blood is real drink." (John 6:55) P2: Jesus often uses figurative language: Christ said more than "This is my body". He said "unless you eat the flesh of the Son of Man and drink his blood, you have no life in you," (John 6:53). Of the three examples given to show that Christ often speaks figuratively, two can be taken quite literally "I am the bread of life," (John 6:48) and "I am the resurrection and the life," (John 11:25). The third was obviously meant to be figurative, "I am the true vine," (John 15:1), since he didn't start sprouting branches or provide a supernatural way for it to happen. Thus, we can see that Christ does not always speak figuratively in this manner, and that when he does it is quite obvious. P3: My words are spirit and life: Let us take a look at this passage again, "...the words that I have spoken to you are spirit and are life," (John 6:63). You will notice first of all that the words are ‘spirit' not ‘spiritual'. Other translations read "…they are full of the Spirit[e] and life". Christ is certainly not trying to say that his very strong and literal language was merely figurative in this verse. On the contrary, looking at the previous verses will show that Christ is telling His doubting listeners that his words are full of the inspiration of the Spirit of God. In addition, if this was what Christ was attempting to say, he did a poor job since many of his disciples left anyways, and this seems very unlikely that God would make such a mistake. http://www.biblegateway.com... P4: Not drink ‘wine' again: Since Christ's blood in the Eucharist is still to all appearances wine, it isn't too strange for him to still refer to it as wine. Catholics today will still often refer to the Eucharist as the host and wine since it just seems to come out naturally. In addition, Christ could have said this to emphasize his point. It is not a pleasant thought to drink blood, while it is a pleasant thought to drink wine. Thus, Christ is using the fact that his blood still appears as wine to emphasize the fact that he will be missing out on the enjoyments of his apostles company during his passion. I look forward to my opponent's rebuttals in the next round and I hope they will be equally as interesting and logical as his past arguments.