Barth on Luther's Doctrine of the Eucharist

In relation to my previous post, I've been reading and enjoying Karl Barth's article "Luther's Doctrine of the Eucharist", written in 1923 and published in Theology and Church. Barth, of course, ultimately disagrees with the direction that Luther took regarding the Lord Supper's, but he remains astonished at the force and boldness of the Reformer's thought. At one point he writes, "It is possible to understand the step which Luther took [with regards to the Lord's Supper] as the act of pure Christian faith in revelation, or as an act manifesting truly demonic force... Actually it was both." Nevertheless, with his penetrating intellect, Barth is able to cut to the heart of the matter as few can. One might even say that he understands Luther better than Luther understood himself, even if he ultimately rejects the Reformer's position.

Barth rightly dismisses the notion (common among Reformed) that Luther's insistence on the Real Presence is an inconsistency in his overall thought, a lingering hangover from medieval Catholicism. "There can be no doubt that what we find here is not a slip in logic, but the purpose which manifests itself with compelling inner necessity... One can say confidently that he would not have been Luther if he had not taken this step."

So what drove Luther irresistibly to the Real Presence? The answer, for Barth, is to be found in Luther's dynamic understanding of the Word. But this insight is misunderstood if the Word is thought to refer only to Christ's words at the Last Supper, "This is my body,... this is my blood." Luther's doctrine of the Eucharist was not merely the product of simple-minded biblical literalism, although later generations of Lutherans have often understood it this way. No, the reason lies deeper. Luther can see Christ's bodily presence in the Eucharist because God's Word is a creative word that establishes the reality it promises. "The word brings with it everything of which it speaks, namely, Christ with his flesh and blood and everything he is and has."

Barth sees this as the truly original aspect of Luther's thought. It is the "predicate of identity", "the identification of the signifying with what is signified, of the sign with the signification." Whereas others played the signum and res of the sacrament against each other, Luther held them tightly together. Another way to say this - citing my earlier post - is that Luther emphasized the signum et res of the sacrament, although he never used this exact formulation. Take the following quote:

"So that this divine promise [of forgiveness] may be to us the most certain of all and render our faith most secure, he set upon it the token and seal which is the most trustworthy and precious of all, as he himself was the price of the promise, his own body and blood under the bread and wine. By this he guarantees that the riches of the promise are given to us; and this requires our acceptance of the promise."

Here it is clear that Luther regards Christ's body as both signum and res: it is what is signified by the bread and wine and it is a "token and seal" of the divine promise of forgiveness. This is not a trivial point for Luther, since it reflects the fact that it is only through Christ's humanity, his body and blood, that we have salvation and the forgiveness of sins. The connection between Christology and the sacrament is clear here. As Luther says, "he himself was the price of the promise." This is the essence of his insistence on the "identification of signifying with what is signified", on the signum et res, and ultimately on the Real Presence itself. The "predicate of identity" is derived from the Incarnation, where the body of Christ both is and signifies our salvation. A disembodied, "spiritual" Christ does not save. Thus, Luther's belief in the Real Presence is nothing more than his belief in the saving power of the Incarnation, where the promise is true because it is "in, with, and under" the flesh.