"Episcopacy" names the ecclesial polity governed by bishops as a distinct office above presbyters. The New Testament, however, uses episkopos (overseer/bishop) and presbyteros (elder) interchangeably for the same office: "And from Miletus he sent to Ephesus, and called the elders [presbyterous] of the church... Take heed therefore unto yourselves, and to all the flock, over the which the Holy Ghost hath made you overseers [episkopous]" (Acts 20:17, 28); cf. Titus 1:5-7. Paul addresses "bishops and deacons" at Philippi with no third order (Philippians 1:1). The development of a three-tier hierarchy (bishop / priest / deacon) appears post-apostolically (Ignatius of Antioch, c. AD 110) but is not clearly mandated in Scripture. Reformed and Presbyterian churches accordingly reject episcopal polity.
Government of the church by bishops; the office and authority of bishops.
EPIS'COPACY, n. Government of the church by bishops; or the office and authority of bishops. Note: The key question is whether the hierarchical episcopate is of apostolic institution or a post-apostolic development.
• Acts 20:17,28 — "He called the elders... Take heed unto yourselves, and to all the flock, over the which the Holy Ghost hath made you overseers."
• Titus 1:5-7 — "Ordain elders in every city... For a bishop must be blameless."
• Philippians 1:1 — "To all the saints at Philippi, with the bishops and deacons."
• 1 Peter 5:1-3 — "The elders which are among you I exhort... Feed the flock of God... taking the oversight thereof."
Episcopacy has been used to consolidate ecclesiastical power far beyond the New Testament pattern.
The historical corruption of episcopacy is the transformation of pastoral office into political hierarchy. What began as servant-leadership became an imperial structure of archbishops, cardinals, and popes. The Reformation recovered the NT pattern of elder-led churches. Yet even Protestant churches fall into episcopal corruption when pastors become authoritarian rulers.
• "The New Testament uses bishop and elder interchangeably for the same pastoral office — it knows nothing of a bishop ruling over multiple churches."
• "The corruption of episcopacy is the corruption of servant-leadership into institutional power."