It was a natural and an easy step to the next point, the Lord's Supper instead of the papal mass. And here opens a new scene of controversy. Opposition is not confined between the reformers and the papacy; on this subject it opens between the reformers themselves. And the zeal that ought to have been exerted unitedly in maintaining a solid front in at tacking the papacy, was in a great measure spent in opposing one another. The contending parties on this subject were Luther on one side, and Carlstadt and Zwingli on the other.
The papal doctrine of the mass is, that the bread and the wine in the sacrament are veritably the actual flesh and blood of the Lord; and that either is as much so as both together; and that therefore it is superfluous to administer both to the laity; and so the bread alone is given instead of bread and wine. This is Trans-substantiation; i.e., "change of substance".
Luther renounced this, and held that although the bread and wine are not the real body and blood of the Lord, yet Christ is really present with the bread and wine. This is Consubstantiation; i.e., "with the substance".
Carlstadt and Zwingli denied both, and held, as is now held by Protestants almost everywhere, that the bread and wine are only memorials of the broken body and shed blood of the Lord Christ.