Overall this is a pretty decent book. One of the most valuable parts here, is that nearly a third of the book is dedicated to how to recognize, evaluate, and weigh evidence and sources for piecing together a historical figure like Jesus. There is a lot of great info on the various approaches, and I appreciate that it's a very reader friendly style, as opposed to Dr. Carrier's book "Proving History," which while a great book as well, is more academic and less accessible to the layperson.
I really enjoyed the historical discussions of the era around the time of Jesus, and of He and His teachings. However, I want to address two minor criticisms I have of this otherwise excellent work.
First, I feel that Ehrman gives way too much credence to the baseless Q source hypothesis. I've dug in deep over the years to find the best arguments for Q, and ultimately it comes down to pure imagination crafting speculative stories about a source that doesn't exist, and almost certainly never did. In fairness, Ehrman does in a couple of places make note that Q is in fact a nonexistent source, but he then still goes on page after page to "quote" this imaginary source. That's simply not possible, and really all he's doing is quoting either Luke or Matthew. Responsible scholarship, not to mention the principle of Ockham's razor, suggests that the simplest explanation is that either Luke used both Mark and Matthew, or that Matthew used Mark and Luke. Luke and Matthew were likely composed within a decade of each other, and they were geographically juxtaposed. One borrowing from the other and adjusting/editing as they see fit, just makes too much sense and explains all the evidence without need for concocting imaginary sources. For more detail on the flaws of the Q hypothesis, I highly recommend Mark Goodacre's book, "The Case Against Q."
Getting the nonsensical Q hypothesis out of the way is important because it ties in to a similar criticism. Ehrman notes the important criteria of independent attestation, also called multiple attestation. This is certainly a critical component in determining the veracity of historical claims, legends, and/or documentation. However, I believe Ehrman is misusing, or at the very least stretching beyond reason, his use of this criteria regarding the gospels and Q. Obviously, calling Q an independent attestation is complete nonsense because Q doesn't exist. Suggesting Q is an independent attestation of some saying or other is as silly as calling an imaginary friend to the stand to independently attest a defendant's story. It's bonkers. Likewise, having four gospels in the biblical canon does not mean that similar sayings between them are multiply or independently attested. This same nonsense appears in the alleged M and L sources hypothesis as well. These are, like Q, completely imaginary and are little more than academic sleight-of-hand attempting to create independent attestation. They're not only without any evidence, but are logically part of an infinite regress fallacy. You end up making up a source for your source, and then "need" a source for that earlier source, which surely must be relying on an earlier source, and on and on ad nauseam. The simple fact is that based on the actual evidence, Mark IS the source, with possible oral traditions passed on as well.
Mark is the earliest gospel, estimated to have been composed in the 70s AD. Matthew is generally thought to have been composed in the 80s AD with Luke being placed somewhere in the 80s to 90s AD. Most scholars understand that both Matthew and Luke used Mark as a source. Right away we have an independent attestation problem. The criteria doesn't work here. When Matthew and Luke use Mark as a source and borrow from Mark to retell similar stories or sayings, that is NOT an independent attestation, and in fact is the opposite because Matthew and Luke are dependent upon Mark as a source. And most scholars that haven't fallen for the imaginary Q story, understand that the similarities between Matthew and Luke are due to one borrowing from the other; again, they are dependent upon one another, not independent attestations. And it's generally understood that Luke borrowed from both Mark and Matthew to compose his gospel, just as he borrowed from Josephus and Homer in composing Acts, all with the apparent goal of creating a cohesive, smooth flowing narrative from Jesus's birth and ministry through to the early church. Luke even tells us this is exactly what he did, using multiple sources (Luke 1:1-4, Acts 1:1-2). Unfortunately most of Ehrman's claims of independent attestation, particularly regarding the gospels and the so-called Q, M, and L sources, are simply erroneous and/or unjustifiably imaginative. They are not independent attestations in any sense, but merely reiterations (retellings) of sayings and stories that are dependent upon other sources.
My other criticism is in regard to Ehrman's Jewish Jesus / Jewish Laws conflations prominent in chapter ten and elsewhere. This is not unique to Ehrman, but I'll address it here. Long story short, Ehrman makes the common error of just throwing similar terms in a blender and using them interchangeably, such as Jew/Jewish, Israel/Israelite, Hebrew, etc. It's important to note, that in order to understand the information he's providing in this chapter, one must realize that all 1st century Jews (ethnic Jews, not the majority who were Idumaean converts) are Hebrews, but not all Hebrews are Jews. In fact, very few Hebrews are Jews. Likewise, all 1st century Jews (again, ethnic Jews, not the majority who were Idumaean converts) are Israelites, but not all Israelites are Jews (most aren't). This is because there WERE no Jews until the father OF the Jews, a son of Jacob named Judah, came to be. It was his lineage that became the (ethnically/genealogically) Jewish people, and prior to him, there were no Jews; but there were Hebrews.
So keeping that important historical note in mind, let's look at an example or two where Ehrman's conflating of the terms can cause confusion. When discussing the argument that Jesus is Jewish, Ehrman states, "Jesus was Jewish. Realizing the Jewishness of Jesus is critical if we are to make sense of his teachings." In actuality, not correctly understanding that Jesus was NOT ethnically Jewish, is precisely what causes so many to not understand His teachings, as I'll show with an example later. Part of the problem comes from the assumption that since His step-father, Joseph, was from the tribe of Judah, then so is He. But this misses some of the key elements of Jesus' entire purpose according to scripture. Jesus was NOT descended from the tribe of Judah in any literal sense. He was only symbolically of Judah via Joseph through a tradition of patriarchal conveyance, but ethnically and genealogically speaking, Jesus was descended from the tribe of Levi through His mother, Mary. He was symbolically of the tribe of Judah through His adoptive step-father, representing His later becoming the Son of God and being anointed Kingly Messiah (Romans 1:3-4, Hebrews 5:5), and genealogically/ethnically of the tribe of Levi through his mother, representing His role as the final High Priest in the Levitical Preisthood. This means Jesus was not Jewish (of Judah), but Levite (of Levi).
So let's look at an example of the type of confusion that can result from not understanding this. Ehrman states, "it was founded by a Jewish teacher who taught his Jewish followers about the Jewish God who guided the Jewish people by means of the Jewish Law. Jesus kept and discussed Jewish customs like prayer and fasting, he worshiped in Jewish places of worship like the synagogue and the Temple, and he kept Jewish festivals like the Passover." This makes it sound like Jesus was part of the Jewish religion, ethnically Jewish, and promoting Jewish law/teaching. And that is NOT accurate at all, as we'll see shortly. What this passage should actually say to make sense of Jesus' teachings, is this; "it was founded by a [Hebrew] teacher who taught his [Hebrew] followers about the [Hebrew/Israelite] God who guided the [Hebrew] people by means of the [Hebraic] Law. Jesus kept and discussed [Hebrew] customs like prayer and fasting, he worshiped in [Hebraic/Israelite] places of worship like the synagogue and the Temple, and he kept [Hebrew] festivals like the Passover." Just because the Jewish leaders also kept some of the Hebraic practices, does NOT mean that those Hebraic practices magically became Jewish ones, nor that Jesus endorsed Judaism when He and they happened to keep the same old Hebraic practices.
This is important in grasping what Jesus' teachings meant because by the 1st century, the Jews had developed the new religion of Judaism (or Judah-ism) which grew from their (the kingdom of Judah) captivity in Babylon, where they began adopting Babylonian mysticism and even exchanging the original Paleo-Hebrew script for the Babylonian Imperial Aramaic script. The new Jewish religion was a syncretic blend of the old Hebraic Torah-based religion, and these new traditions of men borrowed from Babylon. This was the "Jewish Law" of the land in the 1st century (which would become the Talmud & Mishnah), and Jesus was vehemently opposed to it and its practitioners. Jesus taught the original Hebraic/Torah Law (a la Moses) and did keep the Hebrew customs, but the Jewish leaders taught their corrupted Jewish law that blended the Law of Moses with traditions of men (Mark 7:8-13, John 7:19), and this led to the constant conflict between Jesus and the Jewish leaders, resulting in their desire to have Him killed. He was calling out their fake religion and fake piety while on His apocalyptic mission.
So according to the evidence of the Bible, Jesus was not Jewish via religion (at least as an adult), nor was He Jewish via ethnicity/genealogy. He was a Hebrew Levite descendant of Israel, and an adoptive son of Judah through His step-father, Joseph. He was an apocalyptic prophet like many Israelites who came before Him, and one of His primary actions was calling out the Jewish religion and Jewish law that had supplanted God's original Hebraic Law. In fact, because of the "Jewishness" conflation, Ehrman misses a key reason why Jesus was executed. When the Bible speaks of the mocking cry, "Hail King of the Jews!" and talks about the sign on the cross calling Him the "King of the Jews," we need to look closer at the words and context. First, why would Rome care one iota if Jesus claimed to be King of the Jewish people? Answer: They wouldn't. It's not a capital offense any more than claiming to be King of the Pythagoreans. The word translated "Jews" is our problem. It's the Greek word Ioudaion. What your bibles don't tell you, is that that word also means Judeans, as in inhabitants of Judea. There were Jewish people all across the Mediterranean, the Levant, throughout the Roman Empire and beyond. Claiming to be King of these people was absolutely no consequence to Rome, and would be nothing more than a squabble among Jews. However, Judea was a Roman province under Roman rule. Claiming to be King of the Judeans, the inhabitants of Judea, is akin to claiming to usurp Rome's rule. And THAT was a capital offense. Jesus went into Jerusalem, in the heart of Judea, and whether he claimed it or was accused and refused to deny it, was labeled as a man claiming to be the King of the Judeans. The end result was simply inevitable.
In the end, had Ehrman made this distinction of terms, many of his points would have had much more weight and impact regarding Jesus' teachings. I wouldn't say that this "Jewishness" error comes close to breaking Ehrman's argument--he still does a great job at showing Jesus' apocalypticism--but the reader might be left with an incorrect understanding of the underlying motivations behind Jesus' teachings, which are far more fascinating than the rather mundane "another Jewish apocalyptic prophet." Jesus was an old school, Hebrew Torah apocalyptic prophet determined to upend the man-made Jewish religious order which had corrupted the Law of Moses, and it led to not only quite an end to His earthly story, but to the beginning of one of the largest religious stories in mankind's history. And hopefully the reader finds that even among the missteps inevitable in this sort of research.