[Galatians 2:9]
Christ never said His ministry and the ministry of His disciples was intended for the Gentiles to be come "New Israel" (new elect).
Jewish Christians considered Gentile Chritsians in the light Judaism: like Judaism considers Noahite Gentiles, not equals to the Jews.
But Paul went one step beyond simply making the equality sign between them; he actively deconstructed Judaism in his gospel and then tried to sell that as something Christ communicated to him but not to the people hwo faithfully followed Him.
No such attempt is made in the Gospels. Nowehere do the Gospels indicate that Christianity was to be a separate religion from Judaism, or that the Chirstians would not be the Law observing Jews. The idea of taking the message to the Gentiles is an after-taught, out of desperation, and something specifically prohibited by Christ Himself in the Gospels.
Paul literally turned the whole thing upside down and made a whole new religion, claiming, of course revelation after the fullness of Christ came and passed, that Christ was sending him subliminal messages to that effect. We will find out one day if Paul was lying or not, and if we have all been deceived.