The earliest Jesus we meet is that of Paul. This Jesus has many major gnostic qualities ....The Jesus of the author of John is also gnostic,
You would need to specify exactly what you mean by "gnostic" before I could respond to it.
Your claim that John's gospel is gnostic is not only wrong, but ironically so, because there are many points in John's gospels and letters that were clearly written specifically to refute gnostic heresies that were floating around (like the idea that Jesus was never a man in the flesh, or never physically died on the cross).
The earliest Jesus we meet is that of Paul....─ he pre-existed in heaven with God (
Philippians 2:5-8), he created the material universe (1 Corinthian 8:6), and he mediates between that universe and the (immaterial, pure, remote) God. We're told that he's born to a Jewish woman of the line of David but no other details.
None of that is contradicted by anything you'll find in the rest of the NT. And you haven't listed any specific verses you think contradict those.
The Jesus of the author of John is also gnostic, also pre-existed in heaven (
John 6:38,
John 8:58 &c), also created the material world (
John 1:2), also mediates between God and man. As with Paul, no specifics as to how the heavenly Jesus was made flesh, or how he's of the line of David.
The next is the Jesus of Mark. Mark's Jesus is a human born of an ordinary Jewish family, without angelic foretellings or mention of a virgin mother, is not of the line of David,
...
Then come the Jesuses of Matthew and of Luke. There is no suggestion that either pre-existed in heaven. Each of them is angelically foretold, and is born of a virgin (implicitly in Matthew, explicitly in Luke
I must point out up front that many of your issues with the NT are based not on actual contradictions between two different letters, but your issues are based on a single faulty assumption - The assumption that just because an author didn't write about it that they didn't think it happened, or that they didn't believe it. But you cannot assume that is why. It would be wrong to even assume they didn't know about the information they left out, unless you have some reason to suspect they didn't. Especially when there are other explanations that make more sense and fit the evidence better.
For example:
Mark doesn't talk about the more spiritual side of the origin of Jesus OR the earthly virgin birth and Davidic line Matthew talks about - but that doesn't necessarily mean Mark didn't know about or believe in either of those things. You would be wrong to think that Mark just believed Jesus popped up out of no where one day, fully formed, simply because he omitted giving more information on that topic of where Jesus came from. Such a conclusion is not only bad logic, but there are clearly better explanations for why there is a difference in content between the gospels.
The different accounts can easily be harmonized together with all of it being true.
That comes from understanding the context in which these various gospels were written, to whom, and why they were written.
For instance, a difference in audience that reflects a different focus about what was most important to relate to the particular audience of their letter. Or at different points in history there were different theological issues that had to be addressed. There are also variations in which content is included based on the different eyewitness perspectives of the writers involved.
John's is written near the end of his death, after a lot has happened in the church since it's founding and many false teachers have arisen. As such, and with it's Greek audience in mind, an audience that might even be majority gentile church by this point, and even the Jews in the church might be native greek Jews who had more of a greek mindset rather than a hebraic mindset - so you get a focus on different issues that have to be addressed.
It focuses on the spiritual side of Jesus to put to rest the heretical ideas that Jesus might have just a man, or maybe was just a demi-god, or wasn't fully God, or wasn't fully man and was just a spirit. You also see John directly deal with with addressing the idea that John the baptist was the real messiah, which was another strain of false teaching we saw historically pop up early on, by recounting John's own denial of that idea.
There's likely simply no need to talk about the earthly geneaology of Jesus at this time because presumably it simply wasn't an issue of contention by this point by the later Greek church. It was the Judean hebrews who were always most concerned with these issues, which is why Matthew and Hebrews both have a greater focus on these aspects.
It was probably an issue of contention back when Matthew was written, during the early days of the Jerusalem based church, but ceased to be a concern by the time of John's writing, or at least wasn't an issue amount gentile converts or Greek Jews. Especially since that was already established in Matthew's gospel, which very likely was available to them by that time in a Greek translation. That could be another reason John doesn't see the need to retread a lot of the ground Matthew has already covered thoroughly.
Mark is the dictation of Peter's public telling of the Gospel to a Roman audience, presumably to a largely gentile audience. Speaking language is always more simple and abridged for most people, and has more time constraints about the amount you can convey in a single setting, which could also likely why it's the shortest gospel. A speaking format would explain more abridged content focusing on the high points necessary for his audience to come to faith. And Rome as a context makes things like Davidic genealogies, Messianic kingship, and even the fulfillment of certain old testament prophecies, not that relevant to dive into in the context of public preaching because it wouldn't be very meaningful to what is probably a mostly gentile audience or dispersed Jews more disconnected from Judean culture and teaching.
A perfect example of this truth of different audiences is the fact that Matthew is said to be the first Gospel written because it was written to the Jewish converts, before the Gospel went out to the gentiles. This is why in Matthew you find much more focus on the idea of Jesus as Messiah and King, with more focus on referencing Old Testament prophecy, imagery, and Hebraic concepts.
Luke is written as a comprehensive historical and overview, paired with Acts, with a stated aim to increase the reader's confidence in what they have heard by confirming various accounts and information.
and doesn't become son of God until God adopts him at the time of his baptism by John the Baptist,
Matthew, Mark, and Luke don't say that Jesus was adopted as God's son by baptism. They record the voice from Heaven affirming he IS God's son. So there is no textual contradiction with John.
Although everyone else may have to become sons by adoption through baptism into Jesus, that doesn't require that Jesus had the same requirement - we know this by the fact that Jesus was sinless yet still underwent the baptism of John, which was for the remission of sins. John in Matthew 3 affirms that Jesus had no need to be baptized by John, yet Jesus insists it should be done and seems to imply there's more of a protocol or prophectic issue that needs to be followed for other reasons beyond the need for the remission of sins.
It is likely Jesus did this as a prophetic picture or example of what others are to do if they want to follow Him and become like Him, considering that much of what we see Jesus do appears to be done for the sake of demonstrating to us how we are to live by first demonstrating it Himself.
Then Jesus told his disciples, “If anyone would come after me, let him deny himself and take up his cross and follow me.
-Matthew 16
on the model in Psalm 2:7 whereby God adopts David as his son (made even more specific at Acts 13:33).
There's a few problems with your interpretation of that verse.
1. You're talking about adoption, but Acts 13 and Psalm 2 refer to being "begotten". A begotten son is not an adopted son. So Jesus was not adopted. In fact, He is referred to as the "only begotten son of God" by both John and Paul (John 3 and Hebrews 1). That means He proceeded from the Father through the process of conception and birth. Adam can't be called a begotten son of God, even prior to the fall, because Adam was formed from dust with life breathed into him. Adam was not begotten by birth with God giving conception of that birth.
2. Acts 13:33 is not, in context, referring to the baptism of Jesus by John. You're assuming it is, but there's nothing in that passage that would lead you to conclude that. In fact, the context clearly suggests that is not what is being referenced. It is either referring to a time before the world's creation or more likely simply referring to the incarnation of His earthly birth (which does not have to necessarily preclude his pre-existence before an earthly incarnation).
Regardless, Acts 13/Psalm 2 can't be referring to what you claim because Jesus wasn't adopted at any point, he was begotten. And you can't beget someone without a birth. He didn't undergo a birth at the baptism of John, so that's another reason logically the context of Acts 13 cannot be referring to the baptism of Jesus in water by John.
Mark's Jesus is thus the only Jesus whose status as son of God accords with Jewish tradition rather than Greek (though of course Jewish culture had been influenced by Greek thought since Alexander's conquest of the region three centuries earlier, and Greek was the administrative and commercial language of Judea under the Romans.)
Mark's account of the baptism of Jesus is the same as Matthew and Luke; a voice and sign from God affirms Jesus is His Son. So you don't have any reason to claim Mark is communicating something different.
─ an erroneous 'fulfillment-of-prophecy' invention based on the Septuagint, which renders Hebrew `
almah ('young woman') in
Isaiah 7:14 as Greek
parthenos ('virgin'). Both these Jesuses are the result of divine insemination of Mary, a virgin. This means that these two Jesuses have God's own Y-chromosome (so the two incompatible genealogies invented to make Jesus a descendant of David are irrelevant anyway).
There's two problems with your statement:
1. The reading we get of Isaiah 7 doesn't come from the Septuagint's translation, but comes directly from what Luke and Matthew tell us happened; They both say Jesus was born of a virgin, and Matthew says this is a fulfillment of Isaiah 7.
2. There is nothing linguistically wrong with translating Isaiah 7 as "virgin" from the Hebrew word almah. Almah can mean virgin, but doesn't always mean virgin. The Hebrew language actually has no specific language for virgin. They have two or more words for young woman, which often implies unmarried, which by extension usually implies virgin, but we can show in the Bible and historically that none of those words are used exclusively for a virgin. So there's no basis for you to claim that Almah can't be translated as virgin. It is one of the legitimate ways of translating that word.
Contextually there's also reason to believe Isaiah 7 could refer to a virgin; because a young woman giving birth wouldn't be considered a miracle sign from God Himself unless she was a virgin or barren.