The Minimal Jesus Hypothesis (MJH) can be stated in terms of a list of a dozen attributes:
A1. This person was a flesh-and-blood person.
A2. This person was an adherent of Judaism.
A3. This person was a male descendant of the Hebrew people.
A4. This person lived in Palestine as an adult (in his twenties and/or thirties) in the 20s CE.
A5. This person was know to be a preacher of religious beliefs.
A6. This person was known to be a preacher of moral values.
A7. This person was known to be a teacher of religious beliefs.
A8. This person was known to be a teacher of moral values.
A9. This person was crucified in Jerusalem.
A10. This person was crucified by the Romans.
A11. This person was crucified around 30 CE (between 28 CE and 33 CE)
A12. This person was named Yeshu’a.
These are the specific claims that should be confirmed by multiple early and independent historical sources in order for MJH to be considered to be confirmed or highly probable.
However, because the idea of a “Messiah” was a cultural idea that was widespread among Palestinian Jews of the first century, many of the above attributes could have been derived simply from common Jewish beliefs about what the “Messiah” was supposed to be like.
Most adult Americans have a common cultural idea of “Superman” and could write a story about Superman, without consulting any books or written stories about Superman or any movies about Superman, and such stories would contain many common elements (Superman has a red cape and can fly like a jet airplane. Superman has superhuman strength and often uses his special powers to defeat criminals and evildoers, etc.).
Similarly, most adult Palestinian Jews of the first century could create stories about a “Messiah” figure, and those stories would contain many common elements, even if the person creating the story did not use or consult any written documents.
Characteristics (A1) through (A8) can be explained fairly well as being the result of a common cultural idea of a “Messiah”, with the exception of the specific chronological details mentioned in (A8). The chronological details, however, probably cannot be found in all seven of the seven gospel sources that Ehrman points us to, and they probably cannot be found even in all four of the gospel sources that I have been focused on (Mark, Q, L, and M).
Thus, correspondences between the various gospel sources concerning the characteristics (A1) through (A8) provide only very weak evidence for the view that there was an historical Jesus who actually had those characteristics and thereby explains why various independent sources correspond with each other on those characteristics of Jesus.
Thus, it seems to me that Ehrman’s argument really stands or falls on the remaining characteristics (A9) through (A12). These do not appear to be explainable in terms of the common cultural idea of a “Messiah”. So, if all seven gospel sources are independent, and if they all agree on those remaining characteristics, then Ehrman’s argument may have some force, although it would have significantly less force than what it appeared to have initially, when I did not realize there was a plausible alternative explanation available for most of the dozen characteristics showing up in several independent gospel sources.
Most of the remaining characteristics concern the crucifixion of Jesus. There is some redundance here to take into consideration. Crucifixion was (primarily) a Roman punishment, so if one decides that the “Messiah” was crucified, it follows naturally that the crucifixion would be performed by Romans.
Jerusalem also seems like a fairly natural location for the crucifixion, since Jerusalem was not only the most sacred city, for Jews, being the location of the holy Temple, where God (Jehovah) was present, but it was also central politically, in that the wealthy and powerful Jewish priesthood maintained their position of power by collaborating with the Romans. The political conflict between Jews and Romans focused on Jerusalem, and the final battle between Jews and Romans was over the possession and control of Jerusalem.
Death by crucifixion was not what Jews expected to happen to the Messiah. So, the characteristics of Jesus concerned with the crucifixion are not explainable in terms of the common cultural idea of a “Messiah”. However, if some other explanation could be provided to explain why the idea of a crucified Messiah might be present in several of the seven gospel sources, then Ehrman’s first argument would be completely done in. I don’t have such an explanation at this time, but I note this point, because it appears to make the success of Ehrman’s argument precarious.
If just one sentence became somewhat widespread, through oral traditions or word-of-mouth, then the seven gospels argument would be largely undone:
Yeshu’a the messiah was crucified.
The widespread utterance of this one sentence, or very similar sentences, could explain the correspondence of several “independent” gospel sources on the twelve characteristics outlined above, the characteristics defining the Minimal Jesus Hypothesis.
Probably the most significant characteristics are the specific chronological indications, such as the age of Jesus, the date of his ministry, and the date of his crucifixion. If all seven gospel sources independently agree on these chronological points, then that would be significant. But, I think this is not in fact the case. I will need to take a closer look to verify my view, but my impression is that these chronological details are a weak point of Ehrman’s argument.