What do Macedonia and Achaia refer to in Romans 15, and what did those churches do?
In Romans 15, Macedonia refers to northern Greece and Achaia to southern Greece. The churches there made a certain contribution—a collection and offering—for the poor saints, the Jewish believers in Jerusalem, as Paul traveled to minister to them.
Les explains that in Romans 15:25-26, Paul writes that he is going to Jerusalem to minister to the saints, the Jewish believers. Macedonia means northern Greece, and Achaia means southern Greece. Those churches had taken collections and offerings, and it pleased them to make a certain contribution for the poor saints at Jerusalem. Les connects this to Paul and Barnabas being guided by the Holy Spirit to circulate among the Gentile churches and gather collections for the poor Jews in Jerusalem. He also points to 1 Corinthians chapter 16, verse 1, concerning the collection.
But now I go unto Jerusalem to minister unto the saints.