Acts 14:23 says, 'So when they had appointed elders (plural) in every church (singular).' In the days of the original church, each mature assembly was led by a team of biblically qualified elders/pastors, not a single individual. This was a safeguard against many of the probelms we see in churches today. Power corrupts and absolute power corrupts absolutely. Furthermore, in the Bible, there is no differentiation between elders and bishops (literally overseers). This is made clear in Acts 20:17 and 28; Titus 1:5-7; and 1 Peter 5:1-3. The idea of a monarchial bishop ruling over a group of churches was not introduced until after the Apostolic Era. So far as we know, it was first written about by Ignatius of Antioch.