It is my understanding that there is not a single contemporaneous account of either Jesus Christ or anything he said.

As such, the man known as Jesus Christ must be considered a mythical, rather than historical figure.

To which I have to answer, from my limited but currently-expanding knowledge:

Yes, and No.

As far as I've been able to discern, you are correct: There is no independent historical record of Jesus son of Joseph of Nazareth, erstwhile carpenter, later executed for - blasphemy? treason? both? neither? - nor could anything described in the surviving stories have been witnessed by those who wrote them.

Nevertheless, a movement among apocalyptic Judeans of such power to attract a large number of Levantine Gentiles, thus snowballing to the point where, 300 +/- years later, it became the State Religion of the fading Empire, must have had some factual basis at its outset.

And so I must make, as the Fellows of the Jesus Seminar also make, a semantic distinction between the historicity of the radical teacher Jesus and the mythology of the stories written about him (including the words put into his mouth) ex post facto.