In pre‐Christian and extra‐Christian usage the Greek word rendered “bishop,” episkopos, and its cognates, refers primarily to caring for something or someone. This can involve a person's oversight of a task or a group of people, such as priests in a temple, or God's own oversight of a person or an event.
The word occurs rarely in the New Testament and only in later documents with the exception of Philippians 1.1; the other passages are Acts 1.20; 20.28; 1 Peter 2.25; 1 Timothy 3.1–2; Titus 1.7. Acts 1.20 is a citation from Psalm 109.8 used to legitimate the selection of a replacement for Judas among the disciples. Acts 20.28 is from a speech by Paul encouraging his audience to “keep watch … over all the flock, of which the Holy Spirit has made you overseers to shepherd the church of God.” The three citations from the Pastoral Letters have to do with requirements for the position or role of episkopos within the church.
Much of the debate about the usage of the term in the New Testament and early Christianity has been concerned with the evolution of an office called “bishop.” Is it an authoritative role within the church that existed from apostolic times? Or should it be understood as a general term giving some measure of honor and perhaps authority to any believer? Naturally, different Christian traditions have various stakes in how these questions are answered.
With the exception of Philippians 1.1, all of the texts cited above probably come from the very end of the first or the beginning of the second century CE. Acts 20.28 and the citations from the Pastoral Letters seem to have in mind a specific group of leaders who look out for the well‐being of the larger church. Philippians 1.1 seems to have a similar sense; the overseers are mentioned together with deacons, but there is no further indication of how they might have functioned. The Pastorals associate certain responsibilities with the office. The episkopos is a teacher, a good host, possesses only one wife, is above reproach, and perhaps is good in a debate (Titus 1.7); there is no evidence that this overseer had responsibility outside the local church.
The letters of Clement of Rome (ca. 95 CE) and Ignatius of Antioch (ca. 115 CE) demonstrate the development of a hierarchical office that eventually became dominant. The office of bishop is thus an indicator of the evolution of Christianity from a popular Palestinian movement to a sophisticated institution with offices, authorities, and hierarchy.
J. Andrew Overman