Galatians 2:9 And when James, Cephas, and John, who seemed to be pillars, perceived the grace that was given unto me, they gave to me and Barnabas the right hands of fellowship; that we should go unto the heathen, and they unto the circumcision.
Same gospel, two audiences (allegedly)
This was Acts 15.
Acts 17:1 Now when they had passed through Amphipolis and Apollonia, they came to Thessalonica, where was a synagogue of the Jews:
Acts 17:2 And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures,
Acts 18:1 After these things Paul departed from Athens, and came to Corinth;
Acts 18:2 And found a certain Jew named Aquila, born in Pontus, lately come from Italy, with his wife Priscilla; (because that Claudius had commanded all Jews to depart from Rome and came unto them.
Acts 18:3 And because he was of the same craft, he abode with them, and wrought: for by their occupation they were tentmakers.
Acts 18:4 And he reasoned in the synagogue every sabbath, and persuaded the Jews and the Greeks.
See, this is where you guys are dead wrong.
Paul agreed to preach to the uncircumcised, and Peter agreed to preach to the circumcised.
However, that doesn't mean Paul wasn't allowed to preach to the circumcised, nor does it mean Peter wasn't allowed to preach to the uncircumcised. We find examples of both in the Bible.
Paul tells us he preached to the Jew first, and Paul tells us at times he acted like a Jew in doing so. Meaning he didn't eat unclean meat, etc. even though he could have under the NC.