Is the Sermon on the Mount historical?

[unknown soldier]

Did Christ really preach the Sermon on the Mount? I can think of some reasons to doubt the Sermon's historicity. Consider the fact that it appears only in Matthew. Mark, Luke, and John omit it. There are at least three reasons why the Sermon appears only in Matthew:

1. Mark, Luke, and John never heard of the Sermon on the Mount.
2. Mark, Luke, and John knew about the Sermon, but they didn't bother to include it in their gospels perhaps thinking it was unimportant.
3. Matthew made up the Sermon on the Mount.

I think that if Christ really preached the Sermon on the Mount, then 1 and 2 are very unlikely. Eliminating those two possibilities, we are left with 3; Matthew fabricated the Sermon which explains very well why only his gospel includes it. If we want to conclude that the Sermon is historical, then we are left with no good idea why Mark, Luke, and John don't include it.

Maintaining a historical view of the Christ story is laden with difficulties like this. If we see the gospels as works of fiction, by contrast, we can much more easily explain their many peculiarities.

[bjs1]

All four Evangelists knew and valued the Sermon on the Mount, but only ‘Matthew’ thought it was important enough to his audience to include the entire sermon .

I would phrase it that, given the length of a single scroll, writers had to choose which information to include and which information to leave out. For instance Mark, an action-focused Gospel to the Gentiles, did not include lengthy sermons on the Jewish Law such as the Sermon on the Mount.

It's a rather novel look at the gospels.

It’s not. I am building off things that commentators on the Scripture have been saying for at least 1600 years now.

[bluegreenearth]

All four Evangelists knew and valued the Sermon on the Mount, but only ‘Matthew’ thought it was important enough to his audience to include the entire sermon .

I would phrase it that, given the length of a single scroll, writers had to choose which information to include and which information to leave out. For instance Mark, an action-focused Gospel to the Gentiles, did not include lengthy sermons on the Jewish Law such as the Sermon on the Mount.

It's a rather novel look at the gospels.

It’s not. I am building off things that commentators on the Scripture have been saying for at least 1600 years now.

I'm curious to know how the length of a single scroll would actually justify the claim that an author's ability to describe a comprehensive account was limited. After all, the entire Torah was able to be contained within a single scroll made up of 58 sections. So, it seems reasonable to expect that any of the gospel authors would have the same capability of recording detailed and lengthy accounts in one scroll made up of multiple sections or multiple scrolls stored together in a box. This apologetic regarding the limitations set by the length of a single scroll seems like one of those arguments that might appeal to someone who is already inclined to believe the first available explanation without much critical thinking involved.

[bjs1]

All four Evangelists knew and valued the Sermon on the Mount, but only ‘Matthew’ thought it was important enough to his audience to include the entire sermon .

I would phrase it that, given the length of a single scroll, writers had to choose which information to include and which information to leave out. For instance Mark, an action-focused Gospel to the Gentiles, did not include lengthy sermons on the Jewish Law such as the Sermon on the Mount.

It's a rather novel look at the gospels.

It’s not. I am building off things that commentators on the Scripture have been saying for at least 1600 years now.

I'm curious to know how the length of a single scroll would actually justify the claim that an author's ability to describe a comprehensive account was limited. After all, the entire Torah was able to be contained within a single scroll made up of 58 sections. So, it seems reasonable to expect that any of the gospel authors would have the same capability of recording detailed and lengthy accounts in one scroll made up of multiple sections or multiple scrolls stored together in a box. This apologetic regarding the limitations set by the length of a single scroll seems like one of those arguments that might appeal to someone who is already inclined to believe the first available explanation without much critical thinking involved.

Would you prefer “readability”? Or “topical focus”? Or “a largely illiterate society was listening to this being read at once, and Gospels did not have the advantage of being slowly built upon over the course of several centuries”?

Obviously I am simplify the case for the sake of brevity, but any way we look at a single Gospel is going to include some material and leave other material out.

[unknown soldier]

All four Evangelists knew and valued the Sermon on the Mount, but only ‘Matthew’ thought it was important enough to his audience to include the entire sermon .

I would phrase it that, given the length of a single scroll, writers had to choose which information to include and which information to leave out. For instance Mark, an action-focused Gospel to the Gentiles, did not include lengthy sermons on the Jewish Law such as the Sermon on the Mount.

Why couldn't they have used longer scrolls or more than one of the shorter ones?

[bjs1]

All four Evangelists knew and valued the Sermon on the Mount, but only ‘Matthew’ thought it was important enough to his audience to include the entire sermon .

I would phrase it that, given the length of a single scroll, writers had to choose which information to include and which information to leave out. For instance Mark, an action-focused Gospel to the Gentiles, did not include lengthy sermons on the Jewish Law such as the Sermon on the Mount.

Why couldn't they have used longer scrolls or more than one of the shorter ones?

We could go into a discussion of the physical limitation of such scrolls or the writing style of the time or the advantages-verse-disadvantages of keeping to a single scroll, but does it really matter? You already know that, no matter how long the book is, some things were going to be left out.

Rather, look at the style of each Gospel. Try to understand the focus of the Gospel and the intended audience (something I have already discussed a bit in this thread) and you should be able to see why some things were included an others omitted in the individual Gospels.

[Difflugia]

Rather, look at the style of each Gospel. Try to understand the focus of the Gospel and the intended audience (something I have already discussed a bit in this thread) and you should be able to see why some things were included an others omitted in the individual Gospels.

Oddly enough, that's exactly what we keep telling you. Matthew's Jesus is the new Moses and all of the details of his life have been pressed into that mould. Whether or not there was a real guy named Jesus that was the inspiration for the story, the story itself is fictional. Whether it's a retelling of an old story or creation of a brand-new one is an interesting question for historians and New Testament scholars, but almost immaterial to understanding each Gospel itself.

Matthew's accounts of the nativity, the flight to Egypt, and the slaughter of the innocents didn't happen. Those are written as symbolic connections between the life of Jesus and the life of Moses. The sermon on the mount is exactly what we would expect of the new Moses. Was there an actual sermon that Matthew adapted to his story of the new Moses? Maybe, but there are few reasons to think that there really was. It's plausible that some guy gave a sermon that is otherwise just a list of aphorisms, but it's just as likely that saying attributed to Jesus (or that are even just considered to be wise, but otherwise anonymous) were arranged into a fictional address. It's implausible on its face that someone would "ascend into the mountain" to give a sermon that he expected anyone to listen to. If we cast off the parts of the story that are implausible, though, what possible reason is there for thinking that what's left actually happened? Even that is a smokescreen, though. Apologists latch onto the trappings of plausibility in order to slide back in the implausible, or even impossible. I continue finding it darkly funny that the idea of the Gospels being fictional is treated with more scorn than the claim to believe that Jesus was literally born of a virgin, was literally touched by God in the form of a dove, or literally returned from the dead. To pretend (even sincerely to oneself) that these things are historically true is to miss most of Matthew's message.

I challenge you to extend this to the other Gospels. Apologists focus so much on desperate historical harmonization that they miss even intentional differences between Gospels. I pointed out earlier that Luke obviously and intentionally contrasted the sermon on the mount of Matthew's Jesus with the sermon on the "level place" of his own, different Jesus. If Luke thought it important enough to actively change the story, he must have thought it was important. Trying to reharmonize that story with Matthew's is to simply deny that which Luke himself thought was important. Trying to find the one Jesus by harmonizing allegorical details as mundane historical facts is like reading The Old Man and the Sea as the story of someone that got lost while fishing.

• Why did Matthew's holy family flee to Egypt, but Luke's traveled to Bethlehem and back?
• Why did Mark's Gospel end with the empty tomb, but nobody else's did?
• Why did Mark's Jesus cry out on the cross, but Luke's didn't?
• Why did the spirit of God sit upon Matthew's Jesus, but descend into Mark's?
• Why did Jesus of the Synoptics have help bearing his cross, but John's Jesus bore his himself?

These aren't just "gotchas" to be explained away, but important details of the different stories that the authors were telling. If the Bible is telling you of four or more different Jesuses, is it an act of faith to instead believe in a harmonization that is none of them? If your Jesus isn't one of the ones of the Bible, where did he come from?

[bluegreenearth]

Would you prefer “readability”? Or “topical focus”? Or “a largely illiterate society was listening to this being read at once, and Gospels did not have the advantage of being slowly built upon over the course of several centuries”?

Obviously I am simplify the case for the sake of brevity, but any way we look at a single Gospel is going to include some material and leave other material out.

Thanks to the brilliant efforts of textual critics, we now know the gospels you are familiar with were not composed overnight but were built over the course of several centuries. You seem to be falsely presuming the versions of the gospels in your modern Bible are the same stories that the early Christians had at their disposal. Without access to the original versions of the gospels, scholars may only make an educated guess as to what was initially contained in those texts and what was added or removed later by scribes with theological motives.

Also, why was there was a need for multiple different gospels in the first place if the authors are claimed to have been close companions with each other and shared a unifying message of Christianity that was supposed to transcend cultural differences? For instance, when we develop a new process for doing something at my office, my supervisor doesn't ask each of us to write a separate standard operating procedure (SOP) for it. At best, we collaborate together in writing a single SOP. In fact, the desire for a single SOP is so strong among Christians that most sermons about the ministry of Jesus have been and continue to be attempts by theologians to cleverly compile various components from the separate gospels into one coherent message.

If "readability" and "topical focus" were early considerations among these authors, then why was each customized version written decades apart from each other? For example, when the instruction manual for any device is created, the manufacturer doesn't publish the English version first and the Spanish version two decades later followed by the Japanese version ten years after that. Instead, all translations of the instruction manual are published simultaneously. I realize the different translations of an instruction manual are not perfectly analogous to the different gospel accounts, but the same reasoning applies in both cases.

Finally, when the content of each gospel is considered independently and chronologically without artificially harmonizing them all into one Frankenstein account, why is Jesus depicted as four different characters with incongruent personalities? Considerations for the different cultural identities of the intended audiences is insufficient to explain why the character of Jesus progressively and significantly changes between each gospel. If the gospel authors were divinely inspired to essentially record separate but congruent historical accounts of Jesus and his ministry, then isn't it reasonable to expect the four depictions of Jesus's personality to remain consistent regardless of how any other components of the account were tailored to suit each audience? Why is it unreasonable to be skeptical of the gospels' credibility given the fact that the observed pattern of progressive changes between each subsequent account of Jesus's character is consistent with the pattern expected in the development of legends?

[unknown soldier]

We could go into a discussion of the physical limitation of such scrolls or the writing style of the time or the advantages-verse-disadvantages of keeping to a single scroll, but does it really matter?

It matters to you, doesn't it? You brought up the subject of scroll length. I see that now that we debunked your apologetic, you act as if it doesn't matter. Well, scroll length doesn't matter. It was a very lame excuse for why Mark, Luke, and John don't include the Sermon on the Mount.

You already know that, no matter how long the book is, some things were going to be left out.

Would a Lincoln biographer omit the Gettysburg Address? Would a Hitler biographer fail to mention Mein Kampf? Not if they really knew about the people they wrote about. It's simply not likely that if the Sermon is historical, then any gospel would omit it.

Rather, look at the style of each Gospel. Try to understand the focus of the Gospel and the intended audience (something I have already discussed a bit in this thread) and you should be able to see why some things were included an others omitted in the individual Gospels.

Didn't all four gospel writers want to let the world know what Christ preached? Your arguments don't fit anything I've ever had Christians tell me about the gospels.

[Goose]

I'm going to chime in here.

Rather, look at the style of each Gospel. Try to understand the focus of the Gospel and the intended audience (something I have already discussed a bit in this thread) and you should be able to see why some things were included an others omitted in the individual Gospels.

Oddly enough, that's exactly what we keep telling you. Matthew's Jesus is the new Moses and all of the details of his life have been pressed into that mould.

That’s quite badly overstating the argument to say, ”all of the details of his life have been pressed into that mould.” That’s a patently untenable assertion. Frankly, I can’t imagine why one would even assert such a thing. I would agree that Matthew seems to frame Jesus as a kind of new Moses at certain points. Nothing particularly controversial about that. Even conservative scholars have argued for the premise. Matthew was writing to a Jewish audience with an intent to show how Jesus is the fulfillment of scripture. So if one wants to argue something like Matthew framed Jesus as a new Moses giving him a Mosaic flavor whenever the opportunity presented itself, I think something like that kind argument could be made from the evidence. But if you want to argue something along the lines that Matthew’s Jesus was just a rehashing of the life of Moses, then, uh, no.

Whether or not there was a real guy named Jesus that was the inspiration for the story, the story itself is fictional.

Prove it’s fictional.

Whether it's a retelling of an old story or creation of a brand-new one is an interesting question for historians and New Testament scholars, but almost immaterial to understanding each Gospel itself.

It’s not immaterial to the question being asked though. Which is explicitly an historical one – Is the Sermon on the Mount historical?

Matthew's accounts of the nativity, the flight to Egypt, and the slaughter of the innocents didn't happen.

I could simply demand that you prove as well these did not happen using historical methods and watch as your arguments also unravel the rest of history if we apply them to other non-Biblical events. But instead, what I will do is grant this for the sake of argument. Let’s say none of these happened. Let’s say Matthew just made all these bits up.

Those are written as symbolic connections between the life of Jesus and the life of Moses.

That’s one explanation. Another is that they more or less happened and Matthew recorded them in such a way as to highlight the connection for his audience. But let’s go with your explanation. They were nothing more than symbolic connections. Carry on.

The sermon on the mount is exactly what we would expect of the new Moses.

But I think what you want to argue is something like exactly what we would expect of the new Moses if Matthew was recasting his Jesus in the life of Moses. If something like that were the case couldn’t we also expect Matthew to explicitly say Jesus was the new Moses? It’s not that we need an explicit statement from Matthew but it is something we might expect. At the very least we might expect Matthew to mention Moses more times than the other Gospels. But he doesn’t. Matthew mentions the name Moses seven times, Mark eight times, Luke ten times in his Gospel (a further nineteen times in Acts), and John twelve times.

If the sermon on the mount is exactly what we would expect of the new Moses wouldn’t we expect the new Moses to also ascend the mountain, receive a revelation from God, descend the mountain, and then deliver the teaching to the people as Moses did in Exodus (19:21, 25)? Matthew seems to imply the inverse where Jesus ascends, the people follow, and Jesus teaches the people up on the mountain (5:1-2, 28-29).

Aside from the verbiage ἀνέβη εἰς τὸ ὄρος used by Matthew at 5:1 being the same as that used in the Septuagint to describe Moses (Exodus 19:3) there doesn’t seem to be anything concrete to make the link. Perhaps Jesus’ enhancements to the Mosaic law (Matthew 5:21-48) is what we would expect from a new Moses. But I don’t see how that is a necessary expectation. We might also expect the new Moses to simply affirm the Mosaic law at this point. And before we read too much into Matthew’s use of ἀνέβη εἰς τὸ ὄρος at 5:1 let’s keep in mind Matthew also uses very similar verbiage elsewhere (Matthew 14:23, 15:29). Even Mark used similar verbiage (3:13). So, was the verbiage used by Matthew at 5:1 a deliberate signal to make the link with the new Moses? Perhaps. Or perhaps it was just another way to say someone went up the mountain. Or perhaps it was an idiosyncratic way to mean went into the mountainous region.

Was there an actual sermon that Matthew adapted to his story of the new Moses? Maybe, but there are few reasons to think that there really was.

I will give you a very good reason. How about the prior probability that a religious teacher would deliver a sermon? By definition that’s what a religious teacher does, he/she delivers sermons. We know this happens. It happens weekly, if not daily, all around the world in various religions.

It's plausible that some guy gave a sermon that is otherwise just a list of aphorisms, but it's just as likely that saying attributed to Jesus (or that are even just considered to be wise, but otherwise anonymous) were arranged into a fictional address.

It’s more than merely plausible that “some guy gave a sermon” or more likely a series of sermons in this case. The prior probability is a virtual certainty that “some guy gave a sermon” if that guy was a religious teacher.

It's implausible on its face that someone would "ascend into the mountain" to give a sermon that he expected anyone to listen to.

Why is that implausible? We’re not talking about summiting Mount Everest here. We’re talking an ascent up a hill that may have been like this one...
Mount of the Beatitudes

If we cast off the parts of the story that are implausible, though, what possible reason is there for thinking that what's left actually happened?

How about the overwhelming evidence that religious teachers deliver sermons? How about the evidence we have that Jesus was a religious teacher who delivered sermons? How about the snippets of corroborating evidence in Luke that Jesus gave sermons of similar types at a similar point in the narrative (not long before the healing of the centurion’s servant) somewhere on or near a mountain (Luke 6:12-20)? There, that’s three reasons.

Even that is a smokescreen, though. Apologists latch onto a the trappings of plausibility in order to slide back in the implausible, or even impossible.

So far you’ve given nothing that is impossible. The only thing that could pose an impossibility is that Jesus gave the same sermon at the same time at both the top of the mountain and at the bottom. Which calls into question the location, if such a contradiction could be shown. However, that a religious teacher would deliver a sermon, even on a mountain, is hardly implausible.

I continue finding it darkly funny that the idea of the Gospels being fictional is treated with more scorn than the claim to believe that Jesus was literally born of a virgin, was literally touched by God in the form of a dove, or literally returned from the dead. To pretend (even sincerely to oneself) that these things are historically true is to miss most of Matthew's message.

We aren’t talking about a supernatural claim here. We are talking about the mundane claim that a religious teacher gave a sermon. The only peculiarity in and of itself is that this sermon, or at least one of the sermons if Matthew is conflating several sermons into one, was given on a mountain. Well, more like a hill really.

I challenge you to extend this to the other Gospels. Apologists focus so much on desperate historical harmonization that they miss even intentional differences between Gospels.

That may be the case for some apologists but it seems to me bjs, for example, has already conceded intentional differences. And I would too. It seems bjs (and I) have a different explanation for those differences than you do. By the way, harmonizing conflicting historical accounts isn’t just something apologists do. Historians sometimes try to do this as well with other history. I challenge you to try harmonize the narratives of Caesar’s assassination some time.

I pointed out earlier that Luke obviously and intentionally contrasted the sermon on the mount of Matthew's Jesus with the sermon on the "level place" of his own, different Jesus.

Let’s run with this for a moment. Let’s say Luke “obviously and intentionally contrasted the sermon on the mount.” How do you go from there to “his own, different Jesus”? I don’t understand how moving the sermon down the mountain to a level place implies a different Jesus.

If Luke thought it important enough to actively change the story, he must have thought it was important.

We’ll set aside for a moment that you are arguing in a circle here by assuming Luke “actively change[d] the story.” We’ll also set aside for the moment that you are, ironically, strengthening the case for historicity by arguing in the direction of independent attestation. But let’s run with your assertion for the moment. In fact, let’s go even further. Let’s say not only did Luke change the story but he intended to explicitly contradict Matthew on the location of the sermon. Now, how do you get from there to the story was fictional? Go ahead and spell out your logic for me.

Trying to reharmonize that story with Matthew's is to simply deny that which Luke himself thought was important. Trying to find the one Jesus by harmonizing allegorical details as mundane historical facts is like reading The Old Man and the Sea as the story of someone that got lost while fishing.

It’s not even necessary to harmonize the accounts between Luke and Matthew on the location of the sermon or the sermons(s) contents. I can grant the discrepancy on those points. At most such a concession calls into question the exact location of this sermon (or series of sermons?) in relation to the mountain and exactly what was said.

• Why did Matthew's holy family flee to Egypt, but Luke's traveled to Bethlehem and back?
• Why did Mark's Gospel end with the empty tomb, but nobody else's did?
• Why did Mark's Jesus cry out on the cross, but Luke's didn't?
• Why did the spirit of God sit upon Matthew's Jesus, but descend into Mark's?
• Why did Jesus of the Synoptics have help bearing his cross, but John's Jesus bore his himself?

These aren't just "gotchas" to be explained away, but important details of the different stories that the authors were telling. If the Bible is telling you of four or more different Jesuses, is it an act of faith to instead believe in a harmonization that is none of them? If your Jesus isn't one of the ones of the Bible, where did he come from?

Firstly, not one of these is relevant to the question at hand with the possible exception of the first which we can grant for the sake of argument as Matthew painting Jesus as the new Moses. Secondly, at least one of these is simply incorrect. Mark’s account does not merely “end with an empty tomb.” The second to last verse of Mark’s Gospel explicitly states there will be appearances (Mark 15:7). Thirdly, to take these kinds of differences and assert that “the Bible is telling you of four or more different Jesuses” is to blatantly ignore the material the accounts have in common and that each author, like all ancient authors, had his own agenda and audience in mind. It seems a better way of putting it is, the Gospels are telling the story of one Jesus through the eyes of four different authors who each had their own agendas and audiences in mind. Fourthly, a harmonization, if there must be one, is primarily among the secondary details and often done to argue for inerrancy. We could in fact not even attempt a harmonization and still be left with a very orthodox looking Jesus just by focusing on the core aspects recorded in multiple Gospels

[Difflugia]

That’s quite badly overstating the argument to say, ”all of the details of his life have been pressed into that mould.” That’s a patently untenable assertion. Frankly, I can’t imagine why one would even assert such a thing.

If you can't imagine such a thing, then you're in the position of claiming that allegorical fiction isn't a thing (or at least not a Jewish thing). Have you never read, for example, the Testamant of Solomon or 2 Esdras? I would bet money that you've read the books of Job and Ruth. The former two are probably based on historical characters, while the latter two are probably not. I can imagine that there are people even now that believe that some of those are nonfiction, even if I personally find the premise absurd. I would hope, though, that someone that believes that Ruth is genuine history could at least imagine how one might think it isn't. Or am I being too charitable?

I would agree that Matthew seems to frame Jesus as a kind of new Moses at certain points. Nothing particularly controversial about that. Even conservative scholars have argued for the premise. Matthew was writing to a Jewish audience with an intent to show how Jesus is the fulfillment of scripture. So if one wants to argue something like Matthew framed Jesus as a new Moses giving him a Mosaic flavor whenever the opportunity presented itself, I think something like that kind argument could be made from the evidence. But if you want to argue something along the lines that Matthew’s Jesus was just a rehashing of the life of Moses, then, uh, no.

It's good that I didn't claim it's "just a rehashing," then. Jesus was cast as a new Moses character with enough winks from Matthew to the audience to pull us into the story. The fictional Jesus of the Gospels may be the recasting of a historical Jesus, but unfortunately, whether such a Jesus actually existed is lost to us. Since not all fiction (even with partially realistic characters) is based on true stories, the fictional Jesus may not be, either.

Prove it’s fictional.

All four Gospels, Acts, the Pauline epistles, and Revelation include details that cannot be true in a historical sense. The Jesus of history wasn't born of a virgin, didn't turn water into wine, wither a fig tree with his mind, walk on water, have a literal conversation with Moses and Elijah, come back from the dead, mysteriously appear inside of a locked room, levitate to heaven, nor did he speak to anyone from beyond the grave.

Those stories include elements that could be historical by simple virtue of not being impossible, but separating historical bits out of a narrative that's fictional overall isn't as simple as dividing between possible and impossible. If so, then we should think that the inspiration for the fictional Count Dracula, Vlad the Impaler, fed on blood (possible) even though we know he wasn't undead (impossible).

I may also be making a genre mistake in describing as "fiction" hallucinations that are sincerely recounted. In that case, I'm perhaps incorrectly defining Shirley MacLaine's various books as "fiction." If any of your assertions rely on exactly where Out on a Limb falls on the fiction-nonfiction scale, we can discuss it.

Whether it's a retelling of an old story or creation of a brand-new one is an interesting question for historians and New Testament scholars, but almost immaterial to understanding each Gospel itself.

It’s not immaterial to the question being asked though. Which is explicitly an historical one – Is the Sermon on the Mount historical?

With that statement, I was addressing (as I explicitly quoted) the advice to "understand the focus of the Gospel and the intended audience." If that's what we're doing, then we've moved on to the theological message. The sermon's place in the story Matthew wrote isn't dependent on whether an actual Jesus performed the sermon or not. Just as the various versions of the Mosaic covenant described in Exodus and Deuteronomy are important to Judaism whether Moses (and thus the presentation of the covenant) was fictional, so, too, was the oration delivered from the mount, one from "a level place," one shared myth via oral tradition, or one from Matthew's imagination.

But instead, what I will do is grant this for the sake of argument. Let’s say none of these happened. Let’s say Matthew just made all these bits up.

...

The sermon on the mount is exactly what we would expect of the new Moses.

But I think what you want to argue is something like exactly what we would expect of the new Moses if Matthew was recasting his Jesus in the life of Moses. If something like that were the case couldn’t we also expect Matthew to explicitly say Jesus was the new Moses?

We could, but that raises two questions. First, is your assertion correct and second, is that universal (or even common) in allegorical fiction?

The first one's easy; Matthew does explicitly equate Jesus with Moses in 2:14-15:

And he arose, took the young child and his mother by night, departed into Egypt, and was there until the death of Herod that it might be fulfilled which was spoken by the Lord through the prophet, saying, "Out of Egypt did I call my son."

The second question can be addressed with at least one other Moses example from the Bible itself. The "two witnesses" of Revelation 11 are described as having the superpowers of Moses, Elijah, and Elisha. Since superpowers are fictional to begin with, there's not much question that they are intentional references to Moses (as were the powers of Elijah and Elisha in the first place), but the only reference to Moses in Revelation is a single mention of his "song" in 15:3.

If the sermon on the mount is exactly what we would expect of the new Moses wouldn’t we expect the new Moses to also ascend the mountain, receive a revelation from God, descend the mountain, and then deliver the teaching to the people as Moses did in Exodus (19:21, 25)? Matthew seems to imply the inverse where Jesus ascends, the people follow, and Jesus teaches the people up on the mountain (5:1-2, 28-29).

If Matthew were a hack, then you're right, we would. Perhaps he wasn't, though. On the other hand, the corollary to your assertion is that the similarities to Moses (though unattributed anywhere else, including in the other Gospels) are mere historical coincidences.

In a story that already contains a number of elements that cannot be nonfiction, how coincidental are otherwise plausible elements allowed to be before your historical method marks them as suspect?

Aside from the verbiage ἀνέβη εἰς τὸ ὄρος used by Matthew at 5:1 being the same as that used in the Septuagint to describe Moses (Exodus 19:3) there doesn’t seem to be anything concrete to make the link.

So, nothing concrete aside from the phrase appearing verbatim (twice! Exodus 24:18, too) in reference to Moses and nowhere else. Got it.

Note also, that 24:18 also puts Moses in the mountain for "forty days and forty nights," which is also the exact duration that Jesus fasted in the wilderness in 4:2. How concrete would you rate that? Coincidence, perhaps?

Perhaps Jesus’ enhancements to the Mosaic law (Matthew 5:21-48) is what we would expect from a new Moses. But I don’t see how that is a necessary expectation. We might also expect the new Moses to simply affirm the Mosaic law at this point.

Unless Matthew wants the new Moses to introduce a (to coin a phrase) new covenant.

And before we read too much into Matthew’s use of ἀνέβη εἰς τὸ ὄρος at 5:1 let’s keep in mind Matthew also uses very similar verbiage elsewhere (Matthew 14:23, 15:29).

Both of which refer to Jesus in exactly the same way.

Luke does, but only in the pericopes that he took (or replicated by sheer coincidence) from Matthew, one of which he changed in a way that makes his Jesus both less like Moses and more plausible, both of which are (coincidentally, I'm sure) characteristics of the other ways Luke changed Matthew.

Even Mark used similar verbiage (3:13).

Which may or may not have been a Mosaic reference (Mark's references were consistently more subtle than Matthew's), but let's assume it's not. Mark using similar, but not identical wording isn't exactly evidence that Matthew's exact selection of verb tense and word order is coincidence. One might instead conclude that it's evidence of the opposite.

Was there an actual sermon that Matthew adapted to his story of the new Moses? Maybe, but there are few reasons to think that there really was.

I will give you a very good reason. How about the prior probability that a religious teacher would deliver a sermon? By definition that’s what a religious teacher does, he/she delivers sermons. We know this happens. It happens weekly, if not daily, all around the world in various religions.

Which is exactly why a fictional religious leader would give a sermon. Let's even say that Jesus was totally real. What's the prior probability that someone remembered one of his presumably many sermons and reproduced it forty or so years later, compared to that of fictionalizing a sermon that includes sayings of Jesus built up by forty years of oral tradition?

It's implausible on its face that someone would "ascend into the mountain" to give a sermon that he expected anyone to listen to.

Why is that implausible?

You know what? I'll concede that one. The Mount of Olives isn't exactly impassible and was presumably referred to as such before the first century.

If we cast off the parts of the story that are implausible, though, what possible reason is there for thinking that what's left actually happened?

How about the overwhelming evidence that religious teachers deliver sermons?

By that logic, fictional rabbis born of a virgin would, too. One way to determine the overall veracity of a story would be to check the other details.

How about the evidence we have that Jesus was a religious teacher who delivered sermons?

The Gospels, you mean?

How about the snippets of corroborating evidence in Luke that Jesus gave sermons of similar types at a similar point in the narrative (not long before the healing of the centurion’s servant) somewhere on or near a mountain (Luke 6:12-20)?

Considering the similarities that extend to exact phrases, it's pretty hard to argue that Matthew and Luke are independent. That's one of the things historians consider, right?

Even that is a smokescreen, though. Apologists latch onto a the trappings of plausibility in order to slide back in the implausible, or even impossible.

So far you’ve given nothing that is impossible.

Born of a virgin, water to wine, returned from the dead.

We aren’t talking about a supernatural claim here.

Read that part again. I was.