In Part 1 we discussed the literal vs. symbolic interpretation of John 6 in the Bread of Life Discourse. (Click "Part 1" to review if needed.) We left off explaining why a strictly symbolic intperpretation makes no sense.
This brings us to the second question: WHY did the Jews understand Christ literally, and why should we also?
The answer goes back to the beginning of the Pascal Lamb of the Passover and comes to full light as the Old Covenant is fulfilled in the New. There is a WONDERFUL book that goes into the details of this: Jesus and the Jewish Roots of the Eucharist, by Brandt Pitre. I won’t pretend to be able to summarize 240 pages of his book here, so I recommend anyone who wants to delve into this topic to get a copy. I’ll just tap on some Scriptural background.
Something often forgotten in the movie portrayals of the Passover events is a very critical fact: the lamb had to be EATEN. It was not sufficient to sacrifice the lamb and spread the blood on the doorposts. The Pascal lamb had to be eaten in order to complete the Passover. “They shall eat the flesh that night, roasted; with unleavened bread and bitter herbs they shall eat it… In one house shall it be eaten; you shall not carry forth any of the flesh outside the house; and you shall not break a bone of it.” (Ex 12:8, 46)
And what does Jesus do at the Last Supper? He makes Himself this Pascal Lamb. In all of the accounts of the Last Supper, Christ says “take…eat…this is My Body…this is My Blood.” Scripture shows us time and again that Christ is this Lamb: “The next day he saw Jesus coming toward him, and said, “Behold, the Lamb of God, who takes away the sin of the world!” (Jn 1:29) and again in Jn 1:36, “Behold the Lamb of God”. Paul tells us, “Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our paschal lamb, has been sacrificed. Let us, therefore, celebrate the festival, not with the old leaven, the leaven of malice and evil, but with the unleavened bread of sincerity and truth” (1Cor 5:7-8). In fact, Christ is referred to as “the Lamb” more than 25 times in Revelation, such as, “Blessed are those who are invited to the marriage supper of the Lamb” (Rev 19:9).
In the Last Supper, we have Christ’s own words affirming for us that this [the bread and wine offered] IS His Body and Blood. Not once does He say, this “represents” or “is a symbol of”. No, He says, “this IS My Body…this IS My Blood” (cf. Mt 26:26ff, Mk 14:22-24, Lk 22:17-20). And He also tells us to DO this in commemoration of Him. We are to continue to commemorate His once-for-all Sacrifice to make it present to all Christians for all time so that all of us may partake in it. It is a timeless offering that was prophesied by Malachi: “For from the rising of the sun to its setting my name is great among the nations, and in every place incense is offered to my name, and a pure offering; for my name is great among the nations, says the LORD of hosts.” (Mal 1:11) This is a prophecy for a time to come when God’s Name is great “among the nations” and “in every place” from East to West (or morning to night, depending on the translation) “incense” and a “pure offering” are made. What is the ONLY pure offering that can be made to God? It is Christ, as Pascal Lamb, whose once-for-all, and all-sufficient Sacrifice is perpetuated through time to all generations so that all may partake of the Pascal Lamb in the fullest sense: “take, eat”…because in order to be saved, the Passover Lamb had to be EATEN.
That’s PART of the reason why the Jews took Christ literally in John chapter 6. Another part of that answer rests in the Manna from Heaven that Moses brought them, and what they understood about the New Bread of the “New Moses”, the “Christ” to come. Read Pitre’s book if you want more depth and historical facts about that and the other reasons they took Christ literally.
Moving on, Paul talks of this continuing participation in the Supper of the Lamb: “ The cup of blessing which we bless, is it not a participation in the blood of Christ? The bread which we break, is it not a participation in the body of Christ? Because there is one bread, we who are many are one body, for we all partake of the one bread.” (1Cor 10:16-17)
“ For I received from the Lord what I also delivered to you, that the Lord Jesus on the night when he was betrayed took bread, and when he had given thanks, he broke it, and said, “This is my body which is for you. Do this in remembrance of me.” In the same way also the cup, after supper, saying, “This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me.” For as often as you eat this bread and drink the cup, you proclaim the Lord’s death until he comes. Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. Let a man examine himself, and so eat of the bread and drink of the cup. For any one who eats and drinks without discerning the body eats and drinks judgment upon himself.” (1Cor 11:23-29) Note this key point regarding Paul’s literal understanding of the Last Supper. “Whoever…eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord” and “Anyone who eats and drinks without discerning the body eats and drinks judgment upon himself”. If Christ’s Body and Blood are not truly present, then how can one be guilty of profaning Him? Can we eat and drink judgment upon ourselves by eating and drinking mere symbols? No…a symbolic interpretation makes no sense here.
Some Christians cannot bring themselves to a literal understanding of the Eucharist because they can’t “see” Christ there. It just looks like bread. To this I would ask, how many times in Scripture does God reveal Himself in different forms? If God can reveal Himself as a burning bush that never burns up; or as a pillar of smoke and fire before the Israelites; or as the Son of Man, even though He is the God and Creator of all the world; or as a gardener to one of the women who was closest to him…then how difficult is it really for Him to reveal Himself as Bread? Doesn’t that seem all too easy for God to do?
Luke records just such a story to touch on this point in his Gospel account. He later, in his book of Acts, goes on to show us that this “breaking of the bread” becomes a regular part of the Christian life in Acts 2:42, and Acts 20:6-7 “And they devoted themselves to the apostles’ teaching and fellowship, to the breaking of bread and the prayers” and “but we sailed away from Philippi after the days of Unleavened Bread, and in five days we came to them at Tro′as, where we stayed for seven days. On the first day of the week, when we were gathered together to break bread, Paul talked with them, intending to depart on the morrow; and he prolonged his speech until midnight”.
But back to the Gospel account, Luke sums it up nicely for us: In Lk 24:13-35, the story of the 2 Disciples on the road to Emmaus, Christ appears in a form they did not recognize…until they recognize Him “in the breaking of the bread” (Lk 24:35). Luke draws a clear parallel in this account of Christ breaking bread with the 2 disciples and in the Last Supper accounts, in that he records Christ doing 4 specific things: “… he took the bread and  blessed, and  broke it, and  gave it to them” (Lk 24:30, cf. Lk 22:19, Mk 14:22, Mt 26:26). And then after this, “their eyes were opened and they recognized him; and he vanished out of their sight.” (Lk 24:31). Notice it does not say that Christ was no longer there with them. There is no suggestion that Christ left their presence…it says “he vanished out of their sight”, which is a very different concept, theologically, than “leaving” or “no longer being with” someone. Remember, Christ is God, and He is not bound by our limited understanding of our physical existence. The disciples go on to recount their story to the Apostles and tell how, at first they did not recognize Him, but then their eyes were opened “in the breaking of the bread”. (Lk 24:13-35)