The first heresay was the Yiddish claiming the Christ was a “Jew”.

“This is by no means the first defense of the postulate that Christ was not a Jew. Ebionitism, “the earliest of the heresies,” rested upon the same false assumption that is herein called into question. That heresy denounced Paul and the other apostles who carried Christianity to the Gentiles without first converting them to Judaism. The Ebionites were Judeo-Christians–more Jewish than Christian. Hence, this is but a new answer to an old fallacy in the light of the present. In a book of this limited size and well-nigh boundless scope, much must remain unsaid. I have aimed to state the case for the affirmative of my postulate, cover the main points as outlined, and give my conclusions backed by ancient and modern sources.

Timeliness is given to this theme by the recent growth in assertiveness of the Jewish race throughout Christendom. Such growths have been shown by history to have recurred repeatedly, and to have ended invariably in a catastrophe for the Jews. The present tendency in that direction is aggravated by the tacit assent–not to call it timidity–of certain occupants of Christian pulpits, who by their acquiescence in the Jewish boast that they have given us Christ and our religion, put themselves at an enormous disadvantage before the Gentile world, if not in their own consciences. Their place is in the synagogue. What then? Must the Gentile world come to the rescue of Christianity from the clutches of modern Ebionitism as did the Greek Christians before and after the Apostle Paul? We Gentiles have been accused of cowardice for tolerating this situation. A Jewish writer has accused us of cowardice because we have refrained from speaking our minds in all frankness about Judaism and the Jews. Courtesy on the critic’s part might have discovered reasons more compatible with good manners, assuming that he was able to do so.”

• Christ Was Not A Jew by Jacob Conner, 1936, pg.6