Before looking at the arguments themselves, I would like to say something on the scholarly situation, as it bears on the dispute between Licona and Ehrman: Indeed, Licona primes his readers by painting Ehrman as "left of the middle," and recommending Christian scholars Luke Timothy Johnson and Raymond Brown as representing a more conservative but still moderate position. As it happens, I respect both of those scholars, and in fact I agree with Johnson over Ehrman on a number of issues, for instance the authenticity of the Pastoral epistles. I'm not sure how much help it is to mark out a center of the scholarly spectrum, though. New Testament studies seem to me to be hopelessly bothered by ridiculous religious biases on one hand and reactionary skeptical biases on the other. For instance, Licona himself counts among his historical conclusions that Jesus of Nazareth was raised from the dead by unknown powers which originate in a disembodied mind. If this was merely a religious belief on his part that would be bad enough, but he actually travels around the country to speak publicly and debate opponents in support of his view that historians ought to conclude based on their scholarly research that Jesus' corpse was supernaturally reanimated! The far left is considerably better off than that, but still advances conclusions dubious in the extreme (for example the claim that the historical person Jesus never even existed). With such obvious biases at play in the scholarly community, I can't bring myself to trust "the middle" in the same way I would ordinarily do with other branches of history. Instead, I insist on keeping a keen eye on the evidence, and weighing the arguments for myself without much concern for the academic authority (or lack thereof) of the person presenting them. I strongly encourage others to do the same.
To that end, we may investigate some of the arguments on the table in Licona's critique. Laying out his own view of the situation, he cites Eusebius' famous list of Christian Scriptures (Ecclesiastical History 6.20.1) as evidence that the proto-orthodox were quite careful in accepting books as canonical; in particular, he alleges that the "general tendency in the early Church was to exclude rather than include." If this is true, however, it is not evident from the Eusebian passage given. Nor is it obvious from any evidence with which I am presently acquainted. On the contrary, early Christians offered some notoriously bad arguments in support of canonization, for example Irenaeus' argument that we can know the four traditional Gospels are inspired because there are four "principal winds" and four "zones of the world" (Against Heresies 3.11.8), and also the initial acceptance by Serapion of Antioch of the Gospel of Peter as canonical simply because it was attributed to Peter (Eusebius, Ecclesiastical History 6.12). More importantly, however, canonical is not equivalent to authentic; the Church also took as authentic (but not canonical) a good number of dubious writings, for instance the Apostles' Creed and the spurious epistles of Ignatius. While we do know that the proto-orthodox were concerned about the issue of authenticity, I am not aware of any evidence which would indicate that they were in a good position to adjudicate on it. Instead it seems that they based their decisions largely on the perceived doctrinal content of the materials, which is to say that they tended to accept books which supported their theology and reject those which did not---a decidedly poor methodology to the purpose.
Licona next complains that Ehrman's arguments against authenticity are weak and unpersuasive. As an example, he cites Ehrman's contrasting of Eph 2:5-6, where the author takes the resurrection of the dead as having already occurred, and Rom 6:1-4 and 1 Cor 15, where the actual Paul propounds the opposite view that the resurrection is a future event. Licona agrees with Ehrman that the Roman and Corinthian passages do indeed show Paul's vision of a future resurrection. However, he contends that Paul also speaks of the resurrection "in a symbolic sense" in Rom 6:13:
Do not present your members to sin as instruments for unrighteousness, but present yourselves to God as those who have been brought from death to life, and your members to God as instruments for righteousness. (ESV)
He suggests we should interpret Eph 2:5-6 according to the same symbolism. Yet this counter-argument seems to me exceedingly weak. It is true that Paul thought Christians to have escaped in some sense the powers of sin and death, and spoke of this in terms of being "alive to God in Christ Jesus" (Rom 6:11, ESV), and that this is how we ought to interpret Rom 6:13. However, this present-day life in Christ is contrasted with the future physical resurrection of dead bodies, of which Jesus was the "firstfruits," and in which Christians would follow at His second coming (1 Cor 15:20-3, ESV). Eph 2:5-6 seems to address this actual, physical resurrection:
...even when we were dead in our trespasses, made us alive together with Christ---by grace you have been saved---and raised us up with him and seated us with him in the heavenly places in Christ Jesus... (ESV)
So while it is possible that Paul was simply using more symbolism in his epistle to the Ephesians, it seems more natural to me to interpret that particular passage as referring to a literal resurrection of the dead. So it seems that Ehrman is quite right to marshal this as evidence against authenticity. That said, I should add that I don't believe Ehrman's argument is especially compelling on its own. However, he does raise a fair point of evidence against the authenticity of Ephesians which ought to be considered alongside the other evidence available. We are also free to consider Licona's interpretation, which I agree is quite plausible, but this in no way undermines Ehrman's point about the physical resurrection.
Next Licona disputes some of Ehrman's historical observations and conclusions. I find his complaints quite bizarre, however. His most serious allegation is that Ehrman misleads his readers in the following passage:
The New Testament emerged out of these conflicts, as one of the Christian groups won the arguments and decided which books would be included in Scripture. Other books representing other points of view and also attributed to the apostles of Jesus were not only left out of Scripture; they were destroyed and forgotten. As a result, today, when we think of early Christianity, we tend to think of it only as it has come down to us in the writings of the victorious party. Only slowly, in modern times, have ancient books come to light that support alternative views, as they have turned up in archaeological digs and by pure serendipity, for example, in the sands of Egypt. (p183)
Licona openly acknowledges that Ehrman is factually correct, here---"in a technical sense," he adds---but insists that it gives unsuspecting readers the wrong impression nonetheless. Yet he believes that Ehrman here gives the implication that "the only thing distinguishing the literature that made it into the New Testament from the literature that did not is the results of a vote."
This allegation seems to me inexplicable. Does he perhaps think that when Ehrman tells us the early church "decided" on the issue, this somehow suggests a decision by vote? I certainly don't get that image from Ehrman's language. Incredibly, Licona even hints that this may constitute a deliberate deception on Ehrman's part, telling us that "in a book where he is identifying deceit, it's ironic that Ehrman himself engages in misleading his readers." On the contrary, Ehrman wrote an entire volume expressly devoted to clearing up such gross misconceptions, and in which he bluntly countered that "there was certainly no vote to determine Jesus' divinity," and that "the formation of the New Testament canon was instead a long and drawn-out process that began centuries before Constantine and did not conclude until long after he was dead" (Truth And Fiction in the Da Vinci Code, pp15,74).
This is not the only clear instance where Licona has misunderstood Ehrman. For example, in one passage Ehrman wards against the misconception that Christianity was systematically persecuted in the early days of the Roman Empire, writing that, before the year 249 CE, "there were...no declarations that it was illegal, no attempt throughout the empire to stamp it out" (Forged, p164). In response, Licona objects that Nero had Christians executed in 64 CE in Rome, and that Pliny the Younger had the same in Bithynia et Pontus in the early second century. While these events really did occur, they do not seem relevant to the point Ehrman makes in Forged (and other works), which is that we have no evidence of an empire-wide persecution. It appears, then, that Licona has mistaken Ehrman to be saying instead that, in all the empire, there were never any persecutions up to the year 249 CE. Yet this certainly does not follow from anything Ehrman wrote, and on the contrary, it betrays a woeful unfamiliarity with Ehrman's other writings, where he details the persecutions under Nero, Pliny, and numerous others instances of persecution in the empire, including the rooting out of Polycarp in 155 CE, the executions of Perpetua and Felicity in 203 CE, and the persecutions in Lyons and Vienne in the late second century, among others; all of these have been discussed in some length by Ehrman. And even if Licona is ignorant of all this, how could he possibly think a professional scholar of Christian history could be unaware of these events? Does he think Ehrman suddenly forgot all that learned in his many years of training? Licona seems to have no excuse for this grievous error.
Or consider the following description of the book of Acts from Forged, and quoted in Licona's critique:
a book that scholars have as a rule been loath to label a forgery, even though that is what it appears to be (p199)
Despite this clear indication on the part of Ehrman that most scholars avoid calling Acts a forgery, Licona claims that "Ehrman speaks of Acts being a forgery as though this is the conclusion of scholarship." Now, it's not as if Licona simply overlooked on accident Ehrman's denial of this---he quotes it himself! So, why on earth should he think Ehrman to have suggested otherwise? Does he perhaps have the wrong idea about what it means to be "loath" to perform some action? Again, I'm very much perplexed as to what could possibly be the source of his strange views.
Licona continues on to dispute Ehrman's criticism of the book of Acts as historically inaccurate. According to Ehrman, we ought to believe Paul when he outlines in Galatians his movements following his conversion to Christianity. According to that epistle, Paul
went away into Arabia, then back to Damascus, and did not go to Jerusalem for another three years (1:15-19). This makes the story of Paul's conversion in the book of Acts very interesting. Here we are told that Paul is blinded by his vision of Jesus on the road to Damascus; he then enters the city and regains his sight. And what's the very first thing he does when he leaves town? He makes a beeline straight to Jerusalem to see the apostles (Acts 9:1-26). Well, which is it? Did he stay away from Jerusalem, as Paul himself says, or did he go there first thing, as Acts says? (Forged, p205)
According to Licona, this reading of Acts is uncharitable. Instead, he believes we should interpret Acts as a dynamic narrative which tends to "fast-forward" through certain events without comment, though he doesn't give us a reason to prefer his more stilted interpretation. Moreover, he highlights the fact that according to Acts, Paul converted outside Damascus, and then entered the city before moving on. Yet, I would ask, how does this bear on the issue? That is not at all clear to me, but I wonder if Licona is simply confused, here, and thinks that Ehrman believes Acts has Paul going to Jerusalem immediately after his conversion; but as we can clearly see in the quoted passage, this is not at all the case. Instead, the contradiction between Acts and Galatians is just as Ehrman describes it, whereby in Galatians Paul goes (apparently from Damascus or its outskirts) to Arabia first, then back to Damascus, and not to Jerusalem until years later; while in Acts Paul goes inside the Damascus, then to Jerusalem, and never to Arabia. The tension is made worse by Paul's comment in Galatians that he "did not immediately consult with anyone" (1:16, ESV), whereas in Acts it was only three days before he began visiting other Christians and preaching the Gospel in Synagogues (9:3-20). Now, it is certainly possible that the author of Acts simply left out Paul's trip to Arabia, but I can find no evidence in support of this view. Apparently the only reason to prefer Licona's reading is if one is already committed to harmonizing the Biblical accounts, and this is hardly acceptable if we are interested in historical methodologies or indeed truthseeking in general.
Licona's impressive commitment to creatively harmonizing the New Testament is especially evident in his treatment of Acts 9:26-30, where Paul meets with "the apostles" (ESV), despite the fact that Paul expressly tells us in Gal 1:18-20 that he did not meet with any apostle except Peter and James. According to Licona, we can explain this by noticing that
if the Jerusalem Christians were fearful that Paul may have playing a trick on them in order to infiltrate their ranks and identify the key leaders of the entire Christian Church, we can understand why only two leaders were willing to meet with him until they could be certain of the genuineness of his conversion to Christianity. A wise move indeed. No contradiction is necessary.
I cannot help here of being reminded of Heinrich Paulus' colorful interpretations of Jesus' miracles, for example his suggestion that Jesus' walking on water was the result of the disciples' erroneously thinking themselves to be in the middle of the sea when in fact they were just by the shore. Licona's speculations seem no better than that, and so it's difficult to feel any force behind his criticisms of Ehrman.
Despite Licona's many mistakes, not all of his criticisms are completely off-target. He points out that Ehrman himself admits that many of the reasons for thinking the epistles were forged take for granted that they were not extensively modified or otherwise influenced by the thoughts and expressions of secretaries. Yet Ehrman seems unable to provide good reason for making this assumption, except perhaps that there is no precedent for it in Greco-Roman antiquity. However, Licona correctly points out that such an argument is by no means decisive, especially considering that Paul is known to have used secretaries for his undisputed letters. So, this seems to me a valid defense against Ehrman's stylistic charges. On the other hand, just as Ehrman's arguments are not absolutely compelling, neither is Licona's counter-argument. There seems to me no way to decide the issue of a secretary on the basis of the existing evidence, and in the face of this uncertainty we must take stylistic arguments against authenticity to have significant force. Only we must be careful to remember that there is at least one possible explanation to resolve most of them. Fortunately for Ehrman, the most powerful arguments against the authenticity of most New Testament books are not stylistic, but rather based on external data, as well as their substantive (i.e. style-independent) internal content. So Licona's objection isn't going to hold much weight in the face of the totality of the evidence.
In sum, then, it seems plain to me that Licona has allowed his religious biases to get the best of him. His understanding of Ehrman's points appears garbled in many important respects, and as we have seen this too leads him to make a number of serious mistakes in his critique. I am sorry to report then, that as a result, he has little here of value to offer.