Why can't Christians Verify Exactly Where Jesus Was Buried?

[Thumpalumpacus]

To argue otherwise is nonsensical. Let's say we accept that James was written well before Matthew - that means that Matthew somehow took teachings that were spread across a letter and distilled them into a coherent sermon delivered by Jesus - that's illogical as much as anything else.

Not at all. A relatively recent example is Patton's Speech, which he gave several times, with varying verbiage in each instance. A historian took the time to interview soldiers who'd heard it, and using their recollections, reconstructed the speech, in gist if not exact wording. If Matthew had that letter available (and I don't know that he did, nor it relevant to my overarching point that such methodology is not "illogical") --if Matthew had notes covering the key points, he could be able to reformulate the speech, especially if he only had one version to contend with -- such a state of affairs would simplify his task.

For one thing, if that was the case, where did the rest of Jesus's teachings in Matthew come from (that aren't found in Mark)? Because James is very specific and narrow in his use of a small amount of the teaching of Jesus - just as if that writer had listen to that sermon - and perhaps other sermons from Jesus - and then decided which were the important bits he wanted to continue preaching to the followers of Jesus after his death.

Is it not possible for a writer to use more than one source? Indeed, if I were reporting on the man whom I thought to be the son of my god, I'd certainly go to longer lengths than using one source.

Let's say we ignore scholarship that tells us that James is written before any of the gospels, and instead postulate that it's written after Matthew. If that were the case then why does James use such a specific section of the gospel of Matthew, instead of Matthew's broader themes?

Perhaps he wanted to lay emphasis on the made in the SotM? The same way I've snipped the parts of your reply that I both found interesting and could address, perhaps James selected the material that for whatever reason resonated with him?

Therefore if they didn't come up with it, and the three of them all used the teachings found within the Sermons on the Mount/Plain, then it must be that the teachings pre-existed. And that means someone else came up with it - and wouldn't you know it that person was Jesus of Nazareth.

You haven't demonstrated that they didn't come up with it; you've deployed the Argument from Incredulity.

Joseph of Arimathea's tomb is largely irrelevant, because it's a small tomb about the size of a small fireplace that is designed to be use intermittently and not as a final resting place (it's a bit like what a morgue is today, where the body is placed in a shroud and later transferred to an ossuary).

If[/if] Jesus existed, and [i]if he were placed there, might this not possibly explain the Biblical story with appeal to resurrection?