The Heresy of Orthodoxy by Kostenberger and Kruger


As postmodern ideas have taken root in our culture, exclusive truth claims have increasingly come under attack. Jesus is the only way. The Bible is the inerrant, infallible, inspired Word of God. Orthodoxy and heresy exist.

These are not popular ideas. And in academic circles, the desire to debunk these beliefs has been making the rounds for some time—most notably with the publication of German academic Walter Bauer’s work Orthodoxy and Heresy in Earliest Christianity (1934). In this volume, Bauer puts forth the idea that, rather than Christianity being characterized from its earliest days as unified in the preaching of Jesus’ apostles, the earliest Christians were marked by radical diversity. Today, Bauer has found an impassioned advocate in scholar Bart Ehrman, whose books such as Misquoting Truth and Jesus Interrupted, have brought Bauer’s thesis to the popular level—to the point that today, the only heresy is orthodoxy.

That’s why Andreas Kostenberger and Michael Kruger wrote The Heresy of Orthodoxy. In this book, the authors carefully examine the Bauer-Ehrman thesis and seek to show readers why we can trust the Bible and rest in the knowledge that the faith we have is what was taught by Jesus and His Apostles.

Unity or Pluralism: Which Came First?

Divided into three parts, The Heresy of Orthodoxy first deals with pluralism and the origins of the New Testament. How did the Bauer-Ehrman thesis come about? How diverse was early Christianity? And when did heresy first arise?

While the Bauer thesis asserts that different “Christianities” developed in geographical regions and that “the Church Fathers overstated their case that Christianity emerged from a single, doctrinally unified movement” (p. 40), the authors’ brief survey of the available data suggests otherwise. Starting as Bauer did with late first/early second century sources, they reveal a Christianity that is marked by remarkable consistency, particularly when dealing with the person of Jesus Christ. The authors write:

Although the late first and early second century gave birth to a variety of heretical movements, the set of (Christological) core beliefs known as orthodoxy was considerably earlier, more widespread, and more prevalent than Ehrman and other proponents of the Bauer-Ehrman thesis suggest. . . . [W]hen orthodoxy and heresy are compared in terms of genesis and chronology, it is evident that orthodoxy did not emerge from a heretical morass . . . heresy grew parasitically out of an already established orthodoxy. (pp 66-67)

But rather than relying on comparatively late extrabiblical sources as did Bauer, Kostenberger and Kruger investigate the earliest sources we have: The New Testament itself. Their study reveals that, contrary to Bauer and Ehrman, orthodoxy even at that stage was far more widespread and the prevalence of heresy was far too narrow to suggest that there was an even playing field.

In their assertions, the authors are very careful in how they portray the opposing view. While often their incredulity at the poor scholarship is evident, they are careful not to make character judgments. There work is marked by a humble confidence. That’s something I greatly appreciate, especially reading a book with a slightly more academic tone.

Developing the New Testament

Next, the authors address the development of the New Testament: How did we get the books we have? How can we know that these are the right ones? What does the “canon” actually mean?

I greatly appreciated this section as it shed a great deal of light on what the canon is and why it’s important. The authors show that the idea of a canon (a rule or standard of measure) was something that actually preceded and led to the development of the New Testament; it wasn’t something imposed on the documents by later ecumenical councils.

What the authors show is that the New Testament, just as the Old Testament before it, is “at its core, a covenantal document” (p. 112). In fact, a written covenant would have been expected in light of the New Covenant inaugurated with the death, burial and resurrection of Jesus, suggest the authors (p. 113). This understanding, allows us to “move beyond the practice of studying the canon simply by starting in the period of the early church and them moving backward to the New Testament. Instead we can start our studies of canon with the New Testament itself and then move forward to the time of the early church” (p. 124).

As they continue their examination, they conclude that rather than, as suggested by Bauer and Ehrman, that the canon was open until the fourth century and beyond, “the theological convictions of early Christians pointed toward a canon that was restricted to books from the apostolic time period and thus, in principle, ‘closed’ at the very outset” (p. 175).

The historical evidence suggests that under the guidance of God’s providential hand and through the work of the Holy Spirit, early Christians rightly recognized these twenty-seven books as the books that had been given to them as the final and authoritative deposit of the Christian faith. (p. 175)

The authors’ work is sharp and thought-provoking. For those who want or need a primer on the development of the canon, this would be section would be an ideal starting point.

The Reliability of Scripture

Finally, the authors address the most contentious issue: The reliability of the New Testament manuscripts. Can we trust them? Were they altered by scribes for nefarious theological reasons?  How do we know that what the authors originally wrote is what our Bibles say?

This is, perhaps, one of the greatest challenges Christians face today—is the Bible reliable as a historical document? Ehrman would say no for a variety of reasons.

A key issue is that of illiteracy—the suggestion that the vast majority of early Christians were simple peasants and thus unable to read. What modern scholarship reveals, though, is that the early church actually covered a fairly diverse cross section of society. While many early Christians were illiterate, many were also of a fairly high social standing—including the Apostle Paul.

Even then, it’s not safe to assume that social status determines literacy. As the authors point out, “ancient scribes themselves were most often found among the slave class. Members of the wealthy upper class would often not read or write themselves (even though they may have had the ability), but would employ lower-class slaves or scribes to do it for them” (p. 184).

What Kostenberger and Kruger reveal is the seemingly bookish nature of early Christianity—they were not concerned simply with passing on oral tradition and public proclamation, but had developed a “vivid ‘textual culture’ commited to writing, editing, copying, and distributing Christian books, whether scriptural or otherwise” (pp. 200-201). They continue:

[T]here are no good historical grounds for doubting that there were adequate means within the early Christian communities for reliably transmitting books. The only question now is whether the manuscripts themselves are so filled with errors and mistakes that we are forced to doubt their integrity. (p. 201)

While Ehrman in Misquoting Jesus argues that the New Testament documents are so riddled with errors that that there is no way for us to know what the original authors really said, textual criticism and the sheer enormity of the number of documents we have available tell another story. Currently we have well over 5,500 manuscripts of the New Testament—by far the most of any book from antiquity. Ever.

Of these, existing extant documents and fragments date to as early as 35 years after the original writing. The sheer volume of manuscripts and the early dates of many of them is unheard of. While there a great number of variances, the vast majority are insignificant (basically spelling errors and word inversion); things that do not affect the meaning of the passage whatsoever. The number of “significant” variations is relatively small, and most we know about—these are things like the extended ending of Mark, which may not have been original and the story of the woman caught in adultery found in John 7, as well as a few places where the text could say one thing, but it could say another (and these are found in the footnotes in our Bibles).

The authors’ point in addressing these things as thoroughly as they do is to show readers the amazing gift we have in the New Testament manuscripts. No other book from antiquity has been as well preserved, to the point that we have almost too many copies(!). And because of the early dates of many manuscripts and the sheer tonnage of material we have to examine, we can feel confident that we do have contained within our New Testament today, the words the original authors intended.


Kostenberger and Kruger reveal themselves to be scholars par excellence in The Heresy of Orthodoxy. They are thoughtful, deliberate and carefully weigh the evidence available and reach what, if we are being intellectually honest, is an undeniable conclusion: The Bible we have is trustworthy; diversity was not nearly as radical as we are led to believe—and the faith we have today is the same as that which was “once for all delivered to the saints” (Jude 3).

Read the book, wrestle with it, and be assured by it.

Title: The Heresy of Orthodoxy: How Contemporary Culture’s Fascination with Diversity Has Reshaped Our Understanding of Early Christianity
Authors: Andreas J. Kostenberger and Michael J. Kruger
Publisher: Crossway (2010)

A complementary copy of this book was provided for review purposes by Crossway Books

Posted by Aaron Armstrong

Aaron is the author of several books for adults and children, as well as multiple documentaries and Bible studies. His latest book, I'm a Christian—Now What?: A Guide to Your New Life with Christ is available now.

Reader interactions

7 Replies to “The Heresy of Orthodoxy by Kostenberger and Kruger”

  1. […] of it which explains some of the important reasons how and why Walter Bauer's thesis is wrong: Book Review: The Heresy of Orthodoxy by Kostenberger and Kruger The apostate Erhman chose to follow Bauer's falsified hypothesis for the same reason Andrew […]

  2. […] Nothing seems clearer from Scripture itself – from Paul, Jude, Peter and John – than that certain things were not to be believed by Christians.  You can’t read the Johannine Epistles, or Peter or Jude and Paul without seeing quite plainly that certain things were not orthodox – that is not right belief. There’s an excellent series by Professor Michael J Kruger here on the Canon, and his whole website should be read by anyone with an interest in any of these things. There is a compelling, clever and excellent review of Kostenberger and Kruger’s The Heresy of Orthodoxy here (which is, by the way, a font of knowledge and good sense on early Christianity), as well as here. […]

  3. Tudor Georgescu June 6, 2013 at 7:42 am

    “Is orthodoxy theologically correct?” is not a historical question and it cannot be answered by the historical method. While it can be great theology to say that the orthodoxy is right, it is not history. Historians have no access to God and therefore they can never say which belief is theologically correct, if any.

    1. “That history does not takes sides in respect to theological truth claims
      is not an effect of postmodernism, but it is a consequence of proper
      scientific methodology.”

      Your conflating of history with science is unwarranted. History is a form of literature, combining the testimonies of documents, recordings, and archives of archeological records into narratives which reflect both the contents of those records and the considered judgments of the narrator. The narrators will approach their story-telling tasks with particular worldviews which weigh the evidence available to them according to the presuppositions which govern their worldview. The methodologies of science will be useful for only a limited part of that process of assessing and weighing the available evidence. Claiming a “scientific” character for the product of history is a conceit of the worldviews currently dominant in the academy, but this too will pass.

      1. Well stated RR. As Rodney Stark stated, “Science is a method utilized in organized efforts to formulate explanations of nature, always subject to modifications and corrections through systemic observations. Put another way, science consists of two components: theory and research.”

        And, as Alister McGrath stated:

        “The fundamental issue confronting the sciences is how to make sense of a highly complex, multifaceted, multilayered reality. This fundamental question in human knowledge has been much discussed by philosophers of science, and often ignored by those who, for their own reasons, want to portray science as the only viable route to genuine knowledge.

        The natural sciences depend on inductive inference, which is a matter of “weighing evidence and judging probability, not of proof.” Competing explanations are evident at every level of the human endeavor to represent the world-from the details of quantum mechanics to what Karl Popper termed “ultimate questions” of meaning.

        This means that the great questions of life (some of which are also scientific questions) cannot be answered with any degree of certainty. Any given set of observations can be explained by a number of theories. To use the jargon of the philosophy of science: theories are underdetermined by the evidence. The question then arises: what criteria can be used to decide between them, especially when they are “empirically equivalent”? An orthodox atheist would simply revert back to a fundamentalist position that favors their atheistic worldview in the exact same manner as a Muslim or a young earth creationist would revert back to a fundamentalist position that favors their particular worldview.

        The truth is that given the limits of science: science, philosophy, religion and literature all have a legitimate place in the human quest for truth and meaning. This is a widely held view, both in Western culture at large and even within many sections of the scientific community itself. Naturalistic science and other disciplines are not at war. It is the atheist (whose core, incontrovertible, foundational assumption is that there is no God) that places them so and tries to force us to choose between them. Worldviews promoted in such a way leans toward fanaticism.”

  4. […] Incidentally, Andreas J. Köstenberger and Michael J. Kruger’s recent book, The Heresy of Orthodoxy, is a wonderful resource to help better understand the arguments of Dr. Erhman. I reviewed it here. […]

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