I do not know what the earliest Christian biblical new testament writing about Jesus was. And neither do you, or anyone else.
In fact afaik the earliest writing was most probably destroyed or lost.
The closest we can come to a likely fact is that P46 circa 200 AD is probably the earliest relatively complete and readable set of texts that we have, and that apparently contains most of Paul’s letters.
Can we use that text though, according to your standards? P46 is about 150 years after Paul supposedly wrote. It seems to me that the options are:
1) Yes, we can use that text, despite it being a copy and being passed through Christian hands for 150 years, as long as we are aware that interpolations and deletions may have corrupted the text (e.g. as scholars like Ehrman points out)
2) No, we can't use P46 because it is not original and we don't know what changes have been made, etc.
If you choose (1), then you are agreeing with the approach of modern scholars. But you do seem to raise (2) more often than not,
unless you are using it against the historicist position. It seems to me to be a double-standard at best.
So which of the options best represent your approach towards the use of P46? Or do you have a third option?
Now that is most definitely not a description of Jesus as a normal human person ever known to Paul, or ever as a human figure witnessed by any of those 500+ people in that claimed vision.
I have no idea why you keep importing those views into this debate: "normal human person", for example.
My argument is that Paul describes Jesus as a man ("anthropos"), a descendent of the Jews, etc. Of course Paul thought that the man Jesus ascended to heaven and became a supernatural figure. And that supernatural figure is more important to Paul than the man. Paul talks more about the supernatural figure than the man. But still, at the end of the day, Paul talks about Jesus as a man as well.
I think part of the problem is that you are heavily influenced by the Gospel version of Jesus. The Gospels certainly seem to give a lot of importance to Jesus the man, so you assume that Paul must have been the same. But that is not reading Paul for Paul. You are labouring under the same false pretensions that apologists are; you seem to think that it is either "Gospel Jesus" or "no Jesus". Let's examine Paul for Paul. I think you'll see that Paul clearly has Jesus start out as a man, and becomes a supernatural figure. Paul isn't interested in the man, but that component to his view of Jesus is clearly there. That Paul believes Jesus becomes a supernatural figure doesn't somehow invalidate those passages.
In all the gospels he was described, always, as a figure constantly displaying supernatural powers. Normal human people are not supernatural miracle workers who rise from the dead and appear to witnesses whilst communicating from the skies.
I have no idea how that relates to what I have been arguing. It does just come across as preaching, a reflex recital of a position that has nothing to do with the points at hand.
Of course I am not “preaching” to you. Please do not write such silly untrue remarks. I am just pointing out to you (for what must be at least the 100th time, literally), that in P46 (which is what we actually have as “Paul’s letters”) that (i) Paul makes clear he had certainly never met any human person named Jesus, that (ii) he does not name anyone else as ever claiming they had ever met Jesus, that (iii) the description that Paul gives of Jesus is only that of a supernatural religious vision.

You are pointing out to for the 100th time
points that I have never raised nor argued. For the 100th time! I've never argued that (i) Paul met any human person named Jesus, and (ii) Paul names anyone who claims to have met Jesus. Your (iii) is a little more accurate, though even there my argument is that Paul describes Jesus as both a man as well as a supernatural person.
But you have been pointing out for the 100th time things I haven't even been arguing! What more evidence do I need to be able to claim that you are preaching rather than arguing?
As far as the remainder of your post is concerned, i.e. the long discussion of what is said to be the contents of Zechariah and the understanding which Paul and others may or may not have deduced from scripture such as Zechariah - this will require some very lengthy quotes from Carrier's book to explain what he is actually saying about how Paul and other early writers (such as Philo) may have interpreted that scriptural writing to mean the biblical Jesus as a dying and rising son of God. So I will deal with all of that in a separate subsequent post.
I have Carrier's book, so if it helps you can point to pages rather than recite lengthy quotes, which I know is a pain.
But when you do so, can you at least admit that the following statement of yours on the previous page is wrong:
"Carrier says those passages in the book of Zechariah, describe a figure actually named there as “Jesus”, who is a celestial being and described as the Son of God."
I know you said you were quoting from memory, so no harm no foul. But it is worth hitting that nonsense on the head before moving on. The Jesus figure in Zechariah is a man, a high priest. (If you like, he is not a "normal man", because he is part of a vision where he stands before God.)