Continuing "Unified Exegesis?"
We wrote an article here:
And we left off at the time of Luther. The idea here is to show the absurdity that one can claim “The Bible is the sole infallible rule…” without having a massive epistemological problem on their hands.
Reformation Exegesis: One Principle, Many Bibles
When we finally reach the Reformation, we don’t find a clean, unified “biblical method” descending from heaven. We find a cluster of exegetical projects—often sharing slogans (sola Scriptura, sola fide) and sources (Augustine, the Greek and Hebrew texts), yet arriving at sharply divergent doctrinal conclusions.
In other words: the Reformation doesn’t solve the problem of authority by appealing to Scripture alone; it intensifies it.
Humanism and the “Return to the Sources”
On the surface, the Reformers appear to be doing something straightforward: “back to the text.” In practice, that meant three things:
Philological recovery: emphasis on Hebrew and Greek, better manuscripts, better grammar.
Patristic ressourcement: a return not only to the Bible but also to early Fathers, especially Augustine.
Suspicion of late-medieval accretions: a corrective reading of Scripture against certain scholastic conclusions.
David C. Steinmetz’s famous essay “The Superiority of Pre-Critical Exegesis” makes the point that the Reformers were still “pre-critical” in the technical sense: their readings were rooted in the same broad, multi-sense tradition as the Fathers and medievals, even if they gave greater weight to the literal sense and polemicized against some allegorical excesses.
They did not invent a neutral, contextless “plain reading.” They inherited and selectively reshaped an existing interpretive tradition.
Alister McGrath captures this when he notes that the Magisterial Reformers did not reject all tradition, but a specific Roman view of tradition as a second, independent source of revelation. They operated instead with what he calls a “single-source” view: Scripture alone as revelation, but read through “a traditional way of interpreting the biblical text, which does not displace the text.”
The irony is immediate: even where tradition is demoted, a “traditional way of reading” still functions as a norm.
Luther: Scripture Alone and the Preaching Church
Luther’s hermeneutic is often boiled down to “Scripture interprets Scripture” and “what drives Christ.” He insists that the Bible’s clarity lies in its proclamation of Christ, and that obscure texts must be read in the light of clearer ones. But those are already rules—an interpretive filter.
He is fiercely committed to the literal sense against what he views as arbitrary allegory, yet in practice he still uses typology and figural readings in line with the Fathers. Steinmetz’s broader argument is precisely that pre-critical exegesis—Luther included—is comfortable with multiple, layered meanings that modern historical-critical approaches tend to flatten.
Crucially, Luther does not think the Bible floats free in the private judgment of each believer. He sees the preaching office of the Church as the divinely appointed means by which Scripture is proclaimed, and he locates interpretive responsibility heavily in that office. “Scripture alone” never meant “reader alone.”
Yet from the same Bible and the same Christocentric rule, Luther will draw conclusions that other equally Scripture-centered Reformers reject as intolerable.
Zwingli and the Fracturing of the Supper
Nowhere is this more obvious than at Marburg (1529), where Luther and Zwingli face off over four words: “This is my body.”
Luther insists that the verba of institution must be taken with maximal straightforwardness. For him, “This is my body” means Christ’s body is truly, substantially present in the Supper—though without Roman transubstantiation. He is willing to invoke Christ’s divine-human unity and the power of God’s Word to sustain this.
Zwingli, by contrast, argues that the finite human body of Christ is in heaven, and that the Supper is a symbolic memorial and pledge. “Is” must be taken in a metaphorical or sacramental sense, and other texts about Christ’s session at the right hand of the Father must govern the reading.
Both men:
Affirm the authority and sufficiency of Scripture.
Know the original languages.
Reject medieval abuses.
Invoke the Fathers when convenient.
Yet they arrive at mutually exclusive doctrines about a central sacrament. Luther eventually concludes that Zwingli has “another spirit,” while Zwingli fears Luther’s view compromises Christ’s true humanity.
If sola Scriptura were, by itself, a stable, self-authenticating rule of faith, this should not happen. But it does, right out of the gate.
Calvin: Word, Spirit, and Confession
Calvin systematizes Reformation hermeneutics more fully. On the one hand, he sharpens the appeal to the literal-historical sense and produces carefully argued commentaries. On the other, he anchors the certainty of Scripture’s authority in the internal testimony of the Holy Spirit:
“The testimony of the Spirit is more excellent than all reason. For as God alone is a fit witness of himself in his Word, so also the Word will not find acceptance in men’s hearts before it is sealed by the inward testimony of the Spirit.”
That is already a significant shift in where “infallible certainty” is located: not in an external magisterium, but in an internal, divine act.
Yet Calvin does not leave this purely individual. The same Calvin who appeals to the Spirit’s inward witness also institutionalizes doctrine through catechisms and confessions (Genevan Confession, later the French, Belgic, etc.). Richard Muller’s work on post-Reformation Reformed dogmatics shows that, very quickly, Reformed orthodoxy treats Scripture as the primary principium—the first principle of theology—while simultaneously recognizing confessions and church decisions as normative interpretations within that framework.
So again: Scripture is formally the only infallible rule, but in practice it is never naked. It is mediated through confessional standards that acquire a quasi-binding status.
Radical Reformation: From Sola to Solo Scriptura
If the Magisterial Reformers wanted a “middle way” between Roman two-source theory and anarchy, the Radical Reformers pushed in the opposite direction. As Michael Horton and others have noted, what later gets nicknamed solo Scriptura—Scripture as the only authority, not just the only infallible authority—finds some of its earliest expression here.
The Schleitheim Confession (1527), one of the earliest Anabaptist statements, appeals relentlessly to the words of Christ and the New Testament to justify:
Believers’ baptism only (no infant baptism).
Strict separation from “the evil and the wickedness which the devil has planted in the world.”
Non-violence and rejection of the sword: “The sword is ordained of God outside the perfection of Christ… In the perfection of Christ, however, only the ban is used…”
Absolute prohibition of oaths, on the basis of Christ’s command not to swear at all.
These are not marginal ethical quibbles; they reshape baptism, church–state relations, ecclesial discipline, and political participation.
The same Sermon on the Mount that Luther and Calvin take as a binding moral charter is, for them, compatible with magistracy, just war in some cases, and oaths under proper conditions. The Anabaptists, reading the same text with a more rigid literalism and a different view of the Church’s place in history, conclude that any use of the sword by Christians is forbidden and that true believers must withdraw from “the world’s” institutions.
Again, same Bible; radically different ecclesial and ethical worlds.
Scripture at the Center, Divergence at the Edges
We could multiply examples:
Justification: As McGrath notes, the Reformation debate itself centers on the interpretation of Habakkuk 2:4 and Romans 1:17—does “the righteous shall live by faith” refer primarily to God’s faithfulness in Christ or to the believer’s faith and works informed by grace? Catholics and Protestants both appeal to Scripture; they do not share the same exegetical conclusions.
Revelation and eschatology: Irena Backus’ work on Reformation readings of the Apocalypse shows that Geneva, Zurich, and Wittenberg developed markedly different readings of Revelation—historicist, polemical, symbolic—often weaponized against each other and against Rome.
All sides claim fidelity to Scripture. All sides appeal to grammar, context, and theology. All sides accuse the others of “adding” something foreign—philosophy, tradition, human speculation.
What actually differs is how Scripture is located inside a wider network of authorities and assumptions.
Luther leans on the preaching office and an Augustinian reading of sin and grace.
Zwingli leans on a humanist concern for Christ’s true humanity and the spirituality of worship.
Calvin leans on the inward testimony of the Spirit and the stabilizing function of confessions.
Anabaptists lean on a radicalized obedience to the literal commands of Jesus, often against both Rome and the Magisterial Reformers.
The formal principle (“Scripture alone is the only infallible rule”) remains constant on the Protestant side. The exegesis does not.
What This Shows for Our Larger Argument
Taken together, the Reformation era gives us a laboratory demonstration of the central claim of your article:
Even when Scripture is explicitly affirmed as the only infallible rule of faith,
Even when interpreters are highly trained, devout, and immersed in the original languages,
Exegesis still fragments.
It fragments over sacraments, over church structure, over ethics, over eschatology—over “big ticket” doctrines that define visible communion.
That doesn’t mean Scripture is unclear. It means Scripture does not operate in history as a free-floating, self-interpreting authority. It is always mediated by schools, confessions, assumed metaphysics, and living communities that say: “This is what these words mean, and this is what they exclude.”
Which brings us back to the question you’re driving toward: if Scripture is the only infallible rule of faith, who decides what it means when honest, Scripture-bound readers disagree? And on what basis?
The Reformation does not answer that question; it makes it unavoidable.