Bishop: Greek 'Episkopos' lit., an overseer (to look or watch) which has precisely the same meaning, is found in Acts 20:28, Phil 1:1, 1Tim 3:2, 1Pet 2:25
The other Greek word 'Presbuteros' an Elder is another term for the same person as Bishop or overseer.
example: Peter an Apostle said; "I exhort all the elders among you as a fellow-elder"
Bishops/Elders were appointed by the Holy Spirit dispensing their ministerial Gifts as "given" by the ascended Lord Jesus See: Eph 4:8-12, Acts 20:28.
In the early Apostolic churches there was no such position as 'priest or pastor', the church was ministered by the 'collective elder-ship' made up of 'men'... Furthermore; these churches were independent and accountable to the Lord Himself.. We see this in the book of Revelation, where Jesus addresses the seven churches individually, separately bringing them to account. Rev 1:4
These early Apostolic churches were not the 'denominational systems' that we have today.. Denominationalism is the formulation of 'Authoritarian rule' with one man up the top (Pope, Super-intendent, Senior pastor, ect:...
Denominationalism is the 'Babylonian culture' of the Woman/Whore (false religion) seated up top of the beast... Rev 17:3-5
One dares not question the denominational authority without angering the 'Woman' that presides..
That is my experience..
I come out years ago.. The "wilderness" is a beautiful place of worship...