We must remember the entire first church was completely Jewish. Hundreds of thousands of Jews accepted Christ. Peter and Paul took the gospel to the Gentiles and, praise God, many Gentiles accepted Christ. The Jews are God's chosen people because of God's covenant to Abraham. God never broke His promises to the Jews.
Revelation is full of references to the Israelites during the end time.
Another huge misunderstanding in the traditional Christian churches is when a Gentile accuses a Jew of Judaizing. The Bible is clear Gentiles are not to Judaize. If a Gentile believes he earns God's approval by conforming to Jewish practice, he violates the message of Galatians and is involved in true legalism. There are cults that cultivate such legalistic Judaizing of Gentiles. Messianic Jews, with very rare exceptions, are guilty of none of these heresies.