“I indeed admit that the breaking of bread is a symbol; it is not the thing itself. But having admitted this, we shall nevertheless duly infer that by the showing of the symbol the thing itself is also shown. For unless a man means to call God a deceiver, he would never dare assert that an empty symbol is set forth by him. Therefore, if the Lord truly represents the participation in his body through the breaking of bread, there ought not to be the least doubt that he truly presents and shows his body.”
— John Calvin, Institutes of the Christian Religion, 4.17.10, LCC, 2:1371; Quoted in Gregg Allison, Historical Theology, p 654.