François Turretin (1623-1687) was a Genevan-Italian Reformed theologian and one of the authors of the Helvetic Consensus (1675). He is generally considered one of the most prominent Calvinist apologists after John Calvin himself.

In his Institutes of Elenctic Theology, he argued against the Real Presence because of the biblical passages “where the Eucharistic symbols retain the same name after the consecration that they had before (namely, the name of bread and wine).”

He said, “This would not have been done if … they had ceased to be bread and wine and were changed into the body and blood of Christ.”

St. Paul uses the words “eat this bread and drink the cup” (1 Corinthians 11:26) but in the same context also expresses himself literally:

Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. … For anyone who eats and drinks without discerning the body eats and drinks judgment upon himself” (11:27, 29).

He speaks in both ways, both here and in 1 Corinthians 10:16-17 (“The bread which we break, is it not a participation in the body of Christ?”).

Our Lord did the same in John 6:51 (“If anyone eats of this bread, he will live forever; and the bread that I shall give for the life of the world is my flesh”) and in Matthew 26:26 (“Jesus took bread, and ... gave it to the disciples and said, ‘Take, eat; this is my body’”).

So the metaphorical use refers to the accidents of outward appearance, while the literal use refers to transubstantiation and the body and blood of the Lord.

It seems to me the only way to interpret these two complementary motifs is as I have done — or else as Lutherans do, with bread and wine and the body and blood both continuing to be present after consecration. Otherwise, we are left with mere bread and wine being passed out, and no body and blood of Christ at all. This makes Jesus ludicrously being equated with mere bread and wine, and the Bible disallows that.

Note also Paul’s use of “drink the cup” (1 Corinthians 11:26-27). No one can literally “drink a cup” and must drink what it contains. But how do we know what is in this cup? We know by the context and in this instance it highly suggests — rather, virtually demands — a reading that it contains Jesus’ blood. (“In the same way also the cup, after supper, saying, ‘This cup is the new covenant in my blood …’” — 1 Corinthians 11:25). Again, Paul refers in the previous chapter, to “the cup” as “a participation in the blood of Christ” (1 Corinthians 10:16).

It’s the same scenario at the Last Supper (“And he took a cup, and when he had given thanks he gave it to them, saying, “Drink of it, all of you; for this is my blood of the covenant ...” — Matthew 26:27-28). Thus, three times, it’s made crystal clear that we drink Christ’s transubstantiated blood, just as he repeatedly said that we must do to be saved, in John 6.

Beyond these factors, we could also say that the general use of “bread” and “wine” after consecration is simply referring to the appearance, which is what Catholics refer to when we say that these are the “accidents” of the body and blood of Christ. 

Because the Holy Scripture is so clear, the views of the Church Fathers followed suit:

St. Ignatius of Antioch: “The Eucharist [is] the flesh of our Savior Jesus Christ.” (Letter to the Smyrnaeans 7)

St. Justin Martyr: “The food blessed by the prayer of his word ... is the flesh and blood of that Jesus who was made flesh.” (First Apology, chapter 66)

St. Irenaeus: “… the bread which is his body …”  (Against Heresies, V, 2, 3)

Tertullian: ”He declared plainly enough what he meant by the bread when he called the bread his own body.” (Against Marcion, Book IV, chapter 40)

Origen: “You know how, when you have received the Body of the Lord, you reverently exercise care lest a particle fall …” (Homilies on Exodus, 13, 3)

St. Cyprian: “We ask that our bread — that is, Christ — may be given to us daily” (On the Lord’s Prayer / Treatise IV, 18)

St. Athanasius: ”When the great and wondrous prayers have been recited, then the bread becomes the body and the cup the blood of our Lord Jesus Christ.” (Sermon to the Newly-Baptized)

St. Basil the Great: “It is good and beneficial to ... partake of the holy body and blood of Christ.” (Letter XCIII, To the Patrician Cæsaria)

St. Ambrose: “Before the blessing of the heavenly words another nature is spoken of, after the consecration the Body is signified. he himself speaks of his Blood. Before the consecration it has another name, after it is called Blood.” (On the Mysteries, Chapter IX, 50, 52-55)

St. Cyril of Jerusalem: ”After the invocation the Bread becomes the Body of Christ, and the Wine the Blood of Christ ...” (Catechetical Lecture XIX, 7)

St. John Chrysostom: ”‘This is My Body,” he [the priest] says. This statement transforms the gifts.” (Homilies on the Treachery of Judas, 1, 6)

St. Augustine: “For not all bread, but only that which receives the blessing of Christ, becomes Christ’s body.” (Sermons, 234, 2)