[Martin Luther] was uneasy about the theological use of the word fellowship (Gemeinschaft). Even in translating 1 Cor. 10:16 he hesitated to use it. In his Large Confession of the Lord's Supper (1528) he traced the misunderstanding of his opponents partially to this word. "It is not the genuinely German equivalent as I would like to have it, for to have fellowship is ordinarily understood as meaning to have something to do with a person. Here (1 Cor. 10:16), however, it means, as I have explained earlier, many using, enjoying, or having part in a common thing. I have had to translate 'fellowship' because I simply could not find a better word!" He is willing to use the expression "fellowship" of the Lord's Supper only if it is not taken according to the usage of the day, which understood it as "to have something to do with a person." This is not the meaning of the word koinonia in 1 Cor. 10:16, for there it means that many use, enjoy, or have part in a common thing.

This distinction shows what Luther considered vital. What links those who partake of the Lord's Supper is not that they have something to do with one another, their human relationship with each other, but that which they share together. This fellowship not only embraces still another ingredient besides the human participants, but this other ingredient is not even produced by an act of man. It not only antedates the efforts of men, but fellowship (koinonia) means that this is the very element which unites the multitude. What Luther meant is, then, diametrically opposed to what Schleiermacher meant by fellowship when he spoke of the church. For Schleiermacher fellowship "is created by the voluntary actions of men." This is precisely what Luther rejected when he denied that fellowship means "to have something to do with a person."

Werner Elert, Eucharistic And Church Fellowship in the First Four Centuries (Concordia, 1996, 4-5).