“Jesus was not a Jew. He was of Semitic origin as most of the middle easterners are.”
Jesus was most definitely a Jew. It could be said he was not a Judean, however, since He was from Nazareth. To complicate matters the word “Jew” is from “Judea” but that doesn’t change the fact that Jesus was a Jew.
So, being the founder of Christianity means Jesus was jewish?
Modern rabbinical Judaism descends from the Pharisees, who subscribed to the “Oral Torah”, later written down as the Talmud. Jesus rejected the Oral Torah of the Pharisees, which is why they were angry with him. So, by that standard, modern Jews would not accept him as having been a Jew.