Eucharist & Cannibalism

It's a common objection to Catholic teaching on the Eucharist--how can you really believe that you're eating Jesus's body and drinking his blood?  That's cannibalism!

Until recently, I didn't have any better answer to that question if Catholic teaching and John 6 are to be taken literally than "The accidents of bread and wine make a difference.  Also, it's a sacrament--it's not as though we run up to Jesus and start tearing chunks off!"

Then I was on the phone with a friend, discussing this very question, and I realized that, in fact, we don't run up to Jesus and start tearing him apart because we are not being nourished on him from outside of him. 
Listen to the teaching of St. Paul:

For as in one body we have many parts, and all the parts do not have the same function, so we, though many, are one body in Christ and individually parts of one another.  (Romans 12:4-5)

As a body is one though it has many parts, and all the parts of the body, though many, are one body, so also Christ.  For in one Spirit we were all baptized into one body, whether Jews or Greeks, slaves or free persons, and we were all given to drink of one Spirit.  Now the body is not a single part, but many.  If a foot should say, “Because I am not a hand I do not belong to the body,” it does not for this reason belong any less to the body.  Or if an ear should say, “Because I am not an eye I do not belong to the body,” it does not for this reason belong any less to the body.  If the whole body were an eye, where would the hearing be? If the whole body were hearing, where would the sense of smell be?  But as it is, God placed the parts, each one of them, in the body as he intended.  If they were all one part, where would the body be?  But as it is, there are many parts, yet one body. (1 Corinthians 12:12-20)

We are not external to him when we receive Communion--we are members of his body.  We are partaking of his life in the same way that my hand or my eye or my foot partakes of my life.  We drink his blood as my hand or my eye or my foot draws on my blood for nourishment, for life, and for healing.  We are not outside of him tearing him apart, but rather inside of him, part of him, in communion with him and with all the other members of the Body of Christ, sharing in the one flesh, the one blood of the life of the whole body.  We are not members of other bodies from the outside, devouring his flesh and blood, but rather integral parts of the whole Body of Christ.

It's not considered cannibalism when the different organs of my body draw on the same blood supply and are made of the same flesh.  It is not cannibalism when the members of the Body of Christ draw on his flesh and blood for their life and nourishment.