How can I clear up my friend's misunderstanding about the Eucharist?
A friend of mine believes that if he is in a “right” standing with God and prays heavily beforehand, then he is able to have communion with grape juice and crackers or bread, and it would equate to what a priest does at the consecration. He says that he doesn’t need some “guy” blessing some bread and wine/grape juice to have “communion” with his Lord.
The biggest difference between your friend’s understanding of the Eucharist and that of the Catholic Church is that he thinks that we initiate communion with the Lord. Moreover, “if he is in a right standing” with the Lord is a mighty big if! Who determines that—some “guy” like him? Besides sounding a tad arrogant, such a stance is not scriptural (see John 6). Jesus’ apostles didn’t decide to have Communion with him on their own. Jesus initiated the Eucharist and stated quite emphatically that it was truly his body and blood. When most of his disciples left him because of this, there is no evidence that he called them back to explain that he was only speaking symbolically. What the Catholic Church teaches is totally consistent with Scripture (Jn 6:51) and with what the early Church taught.
So the Eucharist is a Communion with the Lord that he established and maintains through the authority he gave to Peter and his successors. Many people have died defending the reality of that Blessed Sacrament. The Communion is both a spiritual union and a physical union that is initiated by Jesus Christ himself—not the result of subjective human fervor. See our tracts on the Eucharist at www.catholic.com/library/sacraments.asp.