Eparchia (G1885) refers to a Roman administrative province — a geographical and political unit governed by a Roman official. It appears twice in Acts (23:34, 25:1) in the context of Paul's legal proceedings: Felix first asked what province (eparchia) Paul was from (Cilicia), and the account of Festus beginning his tenure describes him going to 'the province' (eparchia). The Roman provincial system shaped the spread of the early church.
The eparchia system of Rome became, providentially, a framework for the gospel's spread. Paul moved through Roman provinces (Galatia, Asia, Macedonia, Achaia) deliberately, planting churches in provincial capitals that would radiate outward. The Roman roads, common language (Greek), and provincial administration that made Paul's missionary journeys possible were instruments of God's sovereign timing. What Rome built for empire, God used for Gospel. The kingdom of God (basileia) is not a Roman eparchia — it transcends all human jurisdictions — but it advances through them.