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Argument from Theory Intersection

By:  Erick Nelson
Last Updated:  January 4, 2002

Bishop Spong's latest book, Liberating the Gospels, is an attempt to support the Metaphorical Gospel theory by "seeing the gospels through Jewish eyes."  He says, in essence, "Let's assume that the Metaphorical Gospel theory is indeed true. Let's read the gospels with 'midrashic' understanding, and see how they fit the theory."  At one level, this is a perfectly acceptable preliminary attempt to show that the evidence is consistent with his theory.  It is also one good way to falsify a theory - if the material understood this way fails to fit the theory, we are given reason to reject it.

Spong goes into elaborate detail - including interesting facts regarding the Jewish festival calendar, for instance - as he tries to construct a plausible case.

There is one thing wrong with this extended argument, understood as evidence for the Metaphorical Gospel theory. The particular examples he raises can only give a certain prima facie plausibility to his theory. They can never establish its truth. That is because he commits two fallacies - or, rather, he commits one fallacy, understood in two different ways.

Affirming the Consequent

Spong says, in essence, "If A is true, then B is true. Well, look - B is true. Therefore I conclude A is true." In logic, this is called the fallacy of "affirming the consequent."   

[C.S. Pierce developed a logical system around this, and called it "abduction" (as opposed to deduction and induction).  In probabilistic terms, used carefully, this type of reasoning can indeed have some value.  However, used as we see it here, it is simply a logical mistake.)

To demonstrate that this is indeed a fallacy, it is only necessary to present some examples.

  1. If it is night, it will be dark in my room.
  2. It is dark in my room.
  3. Therefore, it is night.

... is invalid, because it might be day and my shades are drawn.

  1. If the mailman comes, the dog will bark
  2. The dog is barking
  3. Therefore the mailman is here.

... is invalid, because the dog might be barking at something else.

  1. If the gospels were intended metaphorically, we would find a lot of Old Testament themes
  2. We do find a lot of Old Testament themes
  3. Therefore, The gospels were intended metaphorically

... is invalid, because the Jesus might actually be the fulfillment of Old Testament themes.

This kind of argument is actually backward reasoning. From A -> B, it does logically follow that ~B -> ~A (if not-B, then not-A). But it does not logically follow that B -> A.

Arguing from Theory Intersection

Another way to describe Spong's basic logic is to say that he is arguing from "Theory Intersection."  That is to say, he offers evidence which not only supports his own theory but also supports the opposing theory.  It should be obvious that such evidence can never, by definition, show that his theory is right and the opposing theory is wrong!

Let's see what he does. The two basic points Bishop Spong makes are

  1. The New Testament contains many themes which have Old Testament counterparts
  2. At least three of the gospels seem to be ordered in a topical, rather than (strictly) chronological, arrangement, apparently suited for lectionary use.

Usage of Old Testament Themes

I will include one short quote that conveys the general sense of his argument. Spong presents dozens, possibly hundreds, of such examples.

"Matthew certainly believed that he was portraying accurately, if not literally, the teachings of Jesus. However, it is very clear that the Sermon on the Mount was a Matthean creation and was patterned by Matthew on Psalm 119, the psalm of Pentecost. Psalm 119 also began with the word 'blessed.' 'Blessed are those whose way is blameless, who walk in the law of the Lord. Blessed are those who keep his testimonies, who seek him with their whole heart, who also do no wrong, but walk in his ways' (Ps 119:1-3). The whole Sermon on the Mount was a midrashic attempt to reveal Jesus as the new Moses presiding at the new Sinai, the giver of the new law of the new covenant. This sermon gathered together what Matthew believed to be the teaching of Jesus and cast it into the appropriate mold of the Jewish liturgical celebration of Pentecost. It came at the exact spot in Matthew's gospel to fit the Pentecost celebration. It included the proper themes of Pentecost. It was modeled on the psalm of Pentecost. What more powerful proof could be provided that this gospel was written against the background of the liturgical calendar of the Jews?" (Liberating the Gospels, p 115)

Topical Arrangement

Since the 1930's or so, New Testament scholars have commented on the similarities between Matthew's form (arrangement of material) and the Torah. Some scholars were convinced that Matthew represents an attempt to forge a "modern" Torah based on Christian themes. Spong tries to bring us up to date on this.

"B.W. Bacon recognized the uniqueness of these units and was aware of the long-acknowledged Jewishness of Matthew's gospel. He offered the suggestion that Matthew had deliberately punctuated his gospel with five blocks of teaching material in order to suggest that this book was to be a kind of christian Torah." (Liberating the Gospels, p 89)

"It was Michael Goulder, a student of Austin Farrer, who broke the log jam by applying his mentor's insights to a different background. The five teaching blocks in Matthew were not related to the Torah, said Goulder, as attractive as that theory had once seemed. They were related rather, he argued, to the five great celebratory festivals in the Jewish liturgical year. Those festivals were Pentecost (Shavuot), New Year (Rosh Hashanah), Tabernacles (Sukkot), Dedication (Hanukkah), and Passover. . . . The Gospels were not, Goulder asserted, written as 'a literary genre' at all. 'A Gospel is a liturgical genre,' he asserted. The Gospels, at least the synoptics of Mark, Matthew, and Luke, were designed, he argued, to be lectionary books." (Liberating the Gospels, p 91)

According to Spong and Goulder, the Old Testament template for Matthew was not the Torah, but the Jewish festivals. I have no idea whether they are right or wrong - I will assume that they are correct. (It does not follow, however, that a 'liturgical' genre is not one kind of 'literary' genre, however).

Here are some passages from Spong which summarize what he's trying to say, to give you a feel for his point.

"The teaching units of Matthew fall at the five major festivals in the Jewish liturgical calendar. Matthew has front-end loaded Mark because Mark had not covered the first five and a half months of the liturgical calendar. Matthew has provided the exquisite fit of the Sermon on the Mount to cover the one major festival that did not get into Mark's truncated year, which only stretched backward from Passover to Rosh Hashanah, or New Year's.

The organizing principle of Matthew's gospel has been discovered. It was not the life of Jesus or some version of objective history. It was the Jewish liturgical calendar with its festival celebrations. . .

By discovering his organizing principle of the Jewish liturgical year, we are enabled to gaze through this Jewish lens at our Lord in a new way and to begin to see him in a new light." (Liberating the Gospels, p 117-118)

"The Gospel of Luke was written to illumine the Torah with occasional references to the prophets and the psalms, with a bow to the liturgical year of the Jews and with an attempt to harmonize the texts of Mark and Matthew. But above all, it was to illumine the Torah, to show Jesus as the fulfillment of all that Moses wrote. This was the work of a convert to Judaism. He did his work well, so well indeed that only eyes trained to see things from a Jewish perspective will be able to see the meaning of the gospel that bears the name of Luke." (Liberating the Gospels, p 164-5)

"To build this case, it is important first to cite the obvious. The Book of Acts is approximately the same length as Luke and Matthew. Since both of those books were designed to provide a lection per week, as well as to provide for readings to mark the festivals and fasts of the Jewish liturgical year, we can begin with the assumption that the length of the Book of Acts does not disqualify it for consideration as a proper lectionary book. The fact that it is divided into fifty-two lections in the early manuscripts further strengthens that claim. Fifty-two lections would provide a lection per Sabbath of the Jewish year, with enough flexibility to accommodate those added days when the Jewish calendar would be brought into harmony with the Julian calendar, and this enabled the Jewish calendar to remain relatively constant with the annual cycle of darkness and light." (Liberating the Gospels, p 173)

Theory Intersection

[One component of his view is the literary dependence of the gospels upon each other. He follows Goulder, I believe, in affirming a straight succession of gospels - Mark, Matthew, Luke, and John - in which each gospel modifies its predecessor. This is not crucial to his argument, and requires an entire book to address. I will try to cover this topic when I write the article called "Structured Stories with Eyewitness Control."]

Now, Spong provides a real service in noting the extensive parallels between Old Testament and New Testament themes. However, every single bit of evidence he presents equally supports the "other side." "Historic Christians" have from the very beginning, in fact, appealed to this same evidence in supporting their case. I have many times listened to sermons which present Old Testament themes as "shadows of things to come", fulfilled by Jesus. I have often heard that Jesus fulfilled dozens of prophecies at his crucifixion; that Jesus is like Joshua in his victory, like Moses in his authority, like Jeremiah in his suffering, like Isaac in his sacrifice; that Jesus is the 'New Adam', John the Baptist is 'Elijah', and the disciples are like the Twelve Tribes of Israel.

What Spong does, of course, is to turn this argument upside-down. He says that this amazing correspondence is not proof that Jesus fulfilled the Old Testament, but rather is the proof that the stories were simply "borrowed" from the Jewish scriptures and re-used for Christian story-telling.

Whether he's right or wrong, the point is that he is arguing from what I call "Theory Intersection." He is arguing, from the existence of evidence consistent with both theories, that one theory - namely, his - is true. To make this clear, consider this picture:

It is quite possible, and in fact is quite common, for two competing theories to have significantly large areas of evidence with which each is perfectly compatible. Otherwise, they would not both be tenable theories. I represent this by the shaded intersection of A and B.

The thing which distinguishes the correct theory from the incorrect is evidence which supports it, and does not support its competitor. When put this way, in the abstract, this is almost too obvious to mention. In order to prove that A fits the facts, I must come up with some facts which support A and not B. In order to prove that B fits the facts, I must come up with some facts which support B and not A. Therefore, to prove that one of two competing theories is true, I must concentrate not on the evidence supporting both theories (the shaded intersection) but on evidence distinguishing them.

There is, of course, some reason to spend a little time on the shaded area (Theory Intersection) described above. I can, for instance, profitably do this to "keep up" with my opposition. I can turn my opponent's argument against them and show that the evidence also supports my position. However, I can never use this technique to surpass my opposition - I can never show that their theory is wrong as long as I continue to argue from evidence that supports both sides.

The Arrangement of the Gospels

Let's assume that Bishop Spong is correct in assessing the arrangement of the gospel material. Let's say that the gospel stories are indeed arranged in topical order, rather than chronological. What does this prove? Is this a big surprise to believers in "Historic" Christianity? Not at all.

For an example, consider The Little Flowers of Saint Francis, a collection of stories compiled about a hundred years after St. Francis' life. This book was written primarily to inspire rather than merely to document. It's hard to tell how much of the material is historically accurate, and many stories have a "legendary" flavor. It is chock full of miracles. And it is arranged in topical, rather than chronological, order. But this does not make us doubt that the writer intended his readers to construe these are factual accounts.

In the case of the gospels themselves, we have known since the days of Papias (early second century) that the accounts were not necessarily arranged in strict chronological order. (Of course, the general chronological order must be preserved to make sense - the birth before adulthood, trial before crucifixion, death before resurrection, etc. - but the individual accounts need not be.) Papias says,

Mark, having become the interpreter of Peter, wrote down accurately whatsoever he remembered. It was not, however, in exact order that he related the sayings of deeds of Christ. For he neither heard the Lord nor accompanied Him. But afterwards, as I said, he accompanied Peter, who accommodated his instructions to the necessities [of his hearers], but with no intention of giving a regular narrative of the Lord's sayings." (Ante-Nicene Fathers, Fragments of Papias, VI)

It therefore should have come as no surprise to the New Testament scholars who, as early as the 1920's, discovered that the stories existed as "pericopae", small units not necessarily arranged chronologically. Now, does this mean that the stories are not relating facts? Not at all. It only means that they are somewhat topically arranged.

A second point that is often overlooked is the fact that the phrasing of the gospels does not always imply chronological succession. Many times a story is prefaced by "And another time Jesus . . ." .

It turns out that a topical arrangement of the accounts fits the "non-Metaphorical Gospel" equally well. Therefore, Bishop Spong is appealing to the "shaded area" on our chart: Theory Intersection.

Not Theory Intersection?

Yet Spong doesn't feel that this is a case of theory intersection. He tries to present an argument designed to convince us that the "factual" view (he calls it the "literal" view) is inconsistent with the evidence he's found. He says,

"Throughout the ages Christians, treating the Gospels as historical accounts, have drawn some rather interesting literal conclusions from these texts. They assumed, for example, that the public ministry of Jesus was but one year in duration because they did not recognize that the ordering principle of the synoptic Gospels was not the life of Jesus, but the liturgical year of the Jews, which covered that life on an annual cycle. They assumed that Jesus journeyed only once to Jerusalem, and that was for the climactic moments of his life. They assumed that the outline of Jesus' life was covered by the story of the Galilean phase, culminating in the journey and concluding in Jerusalem. It is of interest to note that John countered each of these assumptions in his gospel." (p 95-6)

Now, is this true?  Have Christians predominantly understood from a "historical understanding' of the gospel accounts that Jesus' public ministry lasted just one year?  It does not follow, from the proposition that the synoptics cover only a year of Jesus' ministry, that Jesus' ministry only lasted a year - any more than it follows, from the fact that Mark only describes Jesus' adult life, that he was never a child. If some people have made this mistake, it is not something that is entailed by a "historical" understanding of the gospel accounts. It is something that is caused by poor thinking.

But do people really make this inference in real life? I have, in my experience, never met such a person. I have met two kinds of "Historic Christians":

  1. those who have never thought about how long the ministry was, and
  2. those who are enough aware of John's gospel (which covers about three years of ministry, judging from the festivals Jesus attends) to realize that the synoptics either cover the last year or appear to combine three years into one because they omit references to the various festivals.


Bishop Spong's book presents an extended "Argument from Theory Intersection." If you set aside the several comments expressing his personal views, the parallels between the Old Testament and New are still valid. In fact, ironically enough, this book could be repackaged as a compendium of proofs from fulfillment of Old Testament themes.

His case would have been helped considerably by presenting some direct internal evidence. He could have furthered his cause even more by presenting evidence that didn't equally apply to competing views.