chap, I just want to be clear that my above explanation isn't a condemnation. In that sort of passive-aggressive type coming from Mormonism. Just an explanation.
I understand where you are coming from. The first time a Catholic explained the real presence to me, I called him a cannibal. He in turn, called me a heathen.
It is an acceptance of faith. Christ revealed who He is, I accept that revelation. For myself, my relationship with Jesus Christ is an encounter. The painting shows, artistically, an aspect of that encounter. It is of the heart and soul.
The Eucharist is the source, center and summit of our faith. You'll find many Catholic writings, art and miracles that surround the Eucharist. Some are much more disturbing than a painting. Being provoked, jarred out of our preconceptions and expectations, is one of the attributes of Christ. The Cross, being the prime example.
Some would say, our society (western/US) has sanitized death to the point that it has no affect on us. Don't you think it should? Shouldn't we be provoked?
I'm a simple Catholic. Christ is at the center, always on my horizon. I can't explain others experiences for them. I have had my own, unexplainable, experiences that cannot be explained away as tricks of the mind. Believe me, I tried that route for most of my life. When I asked a Catholic friend, what meaning I should take, what should I do, what, what, what? He only said, why does it have to mean anything more than God's love.
From the writings of mystics that I have read, that is their same approach.
Peace.
Being a Christian is not the result of an ethical choice or a lofty idea, but the encounter with an event, a person, which gives life a new horizon and a decisive direction -Pope Benedict XVI