In today's Gospel reading at Mass, John 6:51-58, Jesus made it absolutely clear in his discourse to the crowds that he is the living bread that came down from heaven and whoever eats this bread will live forever; and this bread is his flesh for the life of the world. The Jews who heard Jesus quarreled among themselves and questioned, "How can this man give us his flesh to eat?" It's obvious that they never doubted that Jesus was not speaking symbolically. Normally, when Jesus told a parable and if there was anything unclear to the listeners, he would explain its hidden meaning. Here, he's not using a parable and there's nothing to explain ~ he simply responded by repeating what he had said, "Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. Whoever eats my flesh and drinks my blood has eternal life... For my flesh is true food, and my blood is true drink. Whoever eats my flesh and drinks my blood..." Even his disciples found the saying hard and difficult to accept; some of them left him. Now, did it strike you for a moment that Jesus didn't literally mean what he said?
The belief that Jesus is truly present in the Holy Eucharist had been held by all since the beginning of the Church. Those today who think that the Lord only offered the bread and wine as symbols are misinterpreting his words to fit their own erroneous belief. In doing so, they miss receiving the most holy of all the sacraments, making it impossible to achieve the most intimate union with him in this life. The Holy Eucharist, Christ himself, is the center of worship in the Catholic Church. Nothing, not even the Bible, can replace that.