According to the NT:
Paul was a Roman Citizen. However he was born and raised a Jew. Paul was very pro-Greek, however, and spent a lot of time in Greece. He himself was not a Greek. Paul's sidekick for a good deal of the time, Timothy, was half Greek.
Peter did not "reject" the Gentiles. Peter did perform some social faux pas like not eating with them around his orthodox friends, and got verbally bitch slapped for it. However it was Peter who first said (to paraphraise) "God showed me in a vision that salvation has come to the Gentiles."
Verses for proof upon request. I don't have them memorized.
"True" Christianity and the bible, good or evil?
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