Quiz: Who wrote the following?

[N.B. -- The answer will appear in a subsequent post.]

The sum is, that the flesh and blood of Christ feed our souls just as bread and wine maintain and support our corporeal life.... This could not be, did not Christ truly ... refresh us by the eating of his flesh, and the drinking of his blood.... Therefore, what our mind does not comprehend let faith conceive .... That sacred communion of flesh and blood by which Christ transfuses his life into us, just as if it penetrated our bones and marrow, he testifies and seals ... and that not by presenting a vain or empty sign, but by there exerting an efficacy of the Spirit by which he fulfils what he promises.... For this reason the apostle said, "The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ?" (1Co 10: 16). There is no ground to object that the expression is figurative, and gives the sign the name of the thing signified. I admit, indeed, that the breaking of bread is a symbol, not the reality. But this being admitted, we duly infer from the exhibition of the symbol that the thing itself is exhibited. For unless we would charge God with deceit, we will never presume to say that he holds forth an empty symbol.