I want to make a couple of points that aren't often emphasized, or even mentioned at all, in discussions about John 6 and the eucharist.
- When John 6 is discussed in relation to the eucharist, the discussion often begins with the comments on the bread of Heaven in verse 31, verse 35, or somewhere else later in the passage. But we should keep the earlier context in mind. Given the contrast that Jesus sets up in John 6:26-29, in which resting in faith in Him is contrasted with the works of the unregenerate that were meant to attain physical benefits, how likely is it that Jesus is about to begin a discussion about attaining eternal life through physical participation in a ceremony that involves eating another type of physical food? Jesus' discourse begins with the contrast between faith and works and the importance of that which is spiritual, and those themes are emphasized again in verses 63-64, shortly after the alleged eucharistic verses. Faith, apart from physical eating and other works, is central to the passage. To read part of the passage as teaching that we attain eternal life through the work of going to a eucharistic ceremony and physically eating Christ's flesh and blood not only is incorrect, but also works directly against what Jesus had said and the context in which He said it.
- I think the weightiest argument for a physical presence of Christ in the eucharist is the popularity of some form of that belief in post-apostolic times. But proponents of a physical presence often overestimate the post-apostolic evidence supporting their position or underestimate the post-apostolic evidence against it. I've discussed some of the patristic evidence in other threads. What I want to do here is mention a line of evidence relevant to some of the earliest fathers, something that isn't often discussed.
When the earliest post-apostolic Christians discussed the issue of cannibalism or responded to the charge of cannibalism brought against Christians (for example, Athenagoras, On The Resurrection Of The Dead, 8; Theophilus of Antioch, To Autolychus, 3:4, 3:15; Minucius Felix, The Octavius, 30), they denied that Christians ever eat any human flesh or drink any human blood. They didn't make an exception for Christ's flesh and blood or attempt to explain that what they do with regard to Christ doesn't have any implications for how they treat human flesh and blood in general. While it would be possible to reconcile such a general denial with a belief in a physical presence in the eucharist, which view of the eucharist makes more sense of such repeated denials that show no concern for exempting Christ or discussing the eucharist? A person who rejects a physical presence in the eucharist could believe in a spiritual presence, so the choice here isn't limited to a physical presence or the symbolic view. And the beliefs of Athenagoras or Theophilus of Antioch don't necessarily reflect the beliefs of, say, Ignatius of Antioch or Cyprian. But the early patristic comments about cannibalism ought to make us more cautious in concluding that early Christian language about the eucharist has the sort of implications that modern proponents of a physical presence suggest. As I think the earlier discussions of John 6 and Ignatius of Antioch illustrate, interpreting the Biblical and patristic passages cited by advocates of a physical presence is often more complicated than they suggest.