The search for the historical Jesus is well known to be one of the most problematic issues in Religious Studies - it's really hard to figure out exactly what, if anything, can be safely asserted about the historical Jesus.
What are you guys' opinions?
Did he exist?
What was he like?
What did he do and say?
The existence of an historical Jesus can't be ruled out.
On that scenario, Paul was right to say that followers of a real Jesus existed as a Jewish sect around 30 CE. Who he was is more difficult to say, and what anyone knew about him is harder still. Historical method discloses one rather persuasive datum ─ In the gospels, with only one exception, Jesus never mentions his mother except in the nastiest terms: Mark 3:31, Mark 6:3, Mark 15:40, Matthew 10:35, Luke 11:27. John 2:3, contrast John 19:26.
Paul says plainly at Galatians 1:11 that he never met an historical Jesus and was never instructed about him by other people. Instead he had a vision ─ that is, everything Paul tells you about Jesus comes out of his own head.
But was there a list of sayings attributed to Jesus, which might be detected in Mark, and as the Q hypothesis suggests for Matthew and Luke? Crossan (a believer), not limiting himself just to the NT, thinks there was, but concludes that precisely which biblical sayings might be authentic can only be guessed at, some guesses having a more promising foundation than others.
(His book
The Historical Jesus: the Life of a Mediterranean Jewish Peasant concludes: "This book, then, is a scholarly reconstruction of the historical Jesus ... one could surely offer divergent interpretative conclusions [to mine] ... But one cannot dismiss it or the search for the historical Jesus as
mere reconstruction, as if reconstruction somehow invalidated the entire project. Because there is
only reconstruction ... If you cannot believe in something produced by reconstruction, you may have nothing left to believe in.")
As a Bart Ehrman fan, I was sorry to be less than persuaded by his
Did Jesus Exist? (2012). It seems principally to rely on the same two things that always seem to be offered: Jesus exists in history because nearly all academics think he did; and Jesus exists in history because Paul refers to James the brother of the Lord (Galatians 1:19), and either emphasizes the point, or undermines his own credibility, depending on your view, by adding "(In what I am writing to you, before God, I do not lie!)" Unfortunately, Paul also used the like expression for others who plainly were not blood kin of Jesus, so even accepted at face value it's not decisive.
So how does doubt arise in the first place? First, by noticing that nowhere in the NT is there even one eyewitness account of an historical Jesus (visions don't count, of course). Nor is there even one contemporary record of him, even though if the gospels are to be believed, he was involved in a trial that involved not only the Sanhedrin, the highest Jewish authorities, but the Roman Prefect himself and in person ─ such matters didn't go unnoticed, yet this one did.
Then there's the chronology. Jesus is generally taken to have been crucified in 30 CE. The first time we meet Jesus in history is in the letters of Paul, written between 51 and (max) 58 CE. (The authenticity of these letters is also disputed, since they were apparently unknown until they were produced in support of Marcion, leader of a gnostic branch of Christians, during Marcion's 2nd century arguments with what are now more mainstream Christians; and Paul is a gnostic. However, I find the character of Paul rather convincingly human, so I don't rush to conclude he's fictitious.)
Paul never met Jesus, and his earthly biography of Jesus fits in a couple of lines ─ Jewish (no parents mentioned), descended from David, had a ministry and followers, preached the Endtimes, introduced the Eucharist, was arrested and crucified (no reason given) and buried.
Not till we get to Mark around 75 CE do we get the only biography of Jesus we have. The author of Mark is not of Paul's school. His Jesus is born of fully human Jewish parents, his birth was not foretold, he's not a descendant of David, his upbringing draws no remarks, and he isn't noticed until John the Baptist washes away his sins, whereupon the heavens open and God adopts him as his son, just as God adopts David as his son in Psalm 2:7 (a point made explicit in Acts 13:33). The author of Mark moves Jesus through a series of episodes that can be mapped onto passages of the Tanakh, as the author takes them to be messianic prophecies, and that's a major part of the problem ─ you don't need an historical Jesus to write a book like Mark.
Then the authors of Matthew, Luke and, at a greater remove, John, take Mark and add to, delete from, and alter it as seems best to each author, including again much fulfillment of purported prophecies. Jesus is no longer a son of Jewish parents. He's got God's Y-chromosome in Matthew and Luke. John's Jesus is gnostic like Paul's ─ both pre-exist in heaven with God, create the material universe, and come to earth to mediate between God and man.
And since Mark doesn't demand an historical Jesus to account for its existence, neither do the other gospels.
If there was one, and if anything about him is reflected in Paul and/or the gospels, then it appears that he was Jewish, from out of town, preached the endtimes like John the Baptist, and was crucified by the Romans.
But then again, Paul (it's thought) is quoting a very early Christian document not of his own making in Philippians 2:6-11, sometimes called the 'Kenosis hymn'. If you read verses 8 and 9 carefully, you'll notice they say that Jesus was not called Jesus till after his death, a sort of title (Yehoshua / Yeshua / Joshua) meaning 'the Lord is Salvation').
And just to stimulate your thoughts, I'll add that the 'hymn' is written as Greek poetry, that is, its lines have a particular scansion; and the scansion is broken by the words in verse 8 "even death on a cross", indicating that they were added later ─ thereby opening up the possibility (not more) that the idea of Jesus dying
on the cross were not part of the original tradition.