We could read today's Gospel as a call to frequent reception of the Eucharist. And John is clearly thinking of the Eucharist at this point in his text. But why is the Eucharist of value? What lies behind it? Into what context should we place it?
John's answer is that the significance of the Eucharist lies in the human life of God. He values the Eucharist because he sees it as a means by which we can engage ourselves with God incarnate. And he thinks that it matters that we do this because he thinks of the Incarnation as leading us to a genuine sharing in God's life.
Make no mistake about it: the Christian vocation is nothing less than a call to become like God. It is about being gathered up into what the Father, the Son, and the Spirit are. And it is the human life of God that began this process. God loved us enough to become one of us so that we may be one with him by being valued as the persons of the Trinity value each other.
Is true life available to us? Well, we certainly live. But we also certainly die. The world, by itself, cannot rescue us from the grave. Yet the grave cannot contain God. He is the Lord of graves. He has true (or full) life, as he shows us by his Son's resurrection.
And, John insists, God's Son (and, therefore, God himself) wants us to share in his lordship over death. He wants us to share in his true life. For he wants us to be united with him and to enjoy what he is about at the core of his being.
In today's Gospel reading, that idea is expressed in the notion of eating Christ's body and drinking his blood. These, John is saying, are true sources of nourishment, sources of true life, just as Christ is one who lives so truly that death has no claim on him. And, for John, all of that is so because Christ is God calling us to be one with him, because God, in Christ, is offering us a share in what it means to be divine.
We do not, of course, know what it means to be divine. Or, at least, we do not know what God is as God knows himself. Yet we do know what God looks like when, so to speak, he projects himself onto history in the figure of Jesus of Nazareth. God's very essence may elude us, but we can readily grasp the story of one like ourselves.
For it is a human story which is not incomprehensible. It can be pictured. It can also be imitated. And the story, the history, of God incarnate is the story, the history, of someone who tells us that true life begins in us when we take him to be its source, when we take him to be even more of a source of nourishment than the food and drink on our tables.
How do we do this? We can do so by receiving the Eucharist. But the Eucharist is not merely human nourishment. Receiving it does not guarantee us true life as, for example, drinking milk guarantees a build up of calcium in us. We celebrate the Eucharist physically to relate ourselves to one who instituted it when coming to the end of a human life with a definite character and goal. We celebrate it to play out in symbols our devotion to him.
But that devotion, if it is to be what he meant by true life, must be more than a matter of play. It must also be a matter of thinking, talking, and acting as he taught us to think, talk, and act. It means taking into ourselves, and therefore making part of ourselves, what he was all about.
The food we eat turns into us. And the food that gives us true life, the Son of God incarnate, is something into which we are meant to turn. Unlike any other, however, this food can turn us into something which nothing else can. It is not easy to digest, but if we grasp and appreciate its ingredients, it can make us to be like God.