Back to the conflict over the Lord's Supper and "Pantheism"

Brecht:  Luther:  Shaping and Refining the Reformation. pp. 311-312

This time Luther wanted to concentrate on the words of institution.  His opponents appeared to him to be quite uncertain of their interpretation.  Once more he pointed out their disagreements, although he knew that there were no substantial differences of opinion between Zwingli and Oecolampadius.  He could easily illustrate how arbitrary the allegorical interpretation was, and he did so with great ridicule.  Several times he demonstrated to the opposing side what sort of absurdities could result from consistently following this "fanaticism."  Luther's strength lay in the text of the words of institution.  The necessity of a symbolic interpretation could not be proved convincingly.  The rational corollary that Christ's body could not be in heaven and in the sacrament at the same time was unacceptable to Luther.  It proved only his opponents' unbelief, which they would not admit publicly, but instead cloaked with rational arguments.
Nevertheless, Luther did discuss the christological problem.  "Sitting at the right hand of God"  was not to be understood in such a way that Christ was bound to a specific place in heaven, but it meant participating in God's omnipotence and omnipresence, which permeated all of creation, down to the tiniest leaf or seed.  Here emerged the realism of Luther's experience of God, derived from the Bible and in no way to be thought of in a pantheistic or metaphysical way.  It was precisely the omnipotent and omnipresent God who had fully entered the Christ who had become man, suffered, and died, and yet who was simultaneously the Son of God with the Father.  Unlike God's creatures, not only was God in this man, but this man himself was God.  Based on this concept of the divine omnipresence, the presence of Christ in the Lord's Supper was not a problem for Luther.  What was new and offensive, however, was his view that Christ's human nature also participated in the attributes of God.  He proved this by the nature of the resurrected Christ's being, which was no longer bound to a particular place or time.  The erroneous conclusion that one could therefore eat the omnipresent Christ everywhere was emphatically refuted.  Only in the Lord's Supper, where he gave himself for the believers, was he tangible to the believer. There he had condescended to come to sinners.  This, however, did not lessen his majesty.  The objections raised by the opposing side only revealed their lack of understanding and unbelief.