St Sixtus II (bishop) ordains St Lawrence (deacon)
Bishop, Priest, and Deacon - What do these words mean? All three come from Greek words and derive from the Greek New Testament.
Bishop comes from the Greek word episkopos, meaning "overseer." The prefix "epi-" means "upon" and "scopus" means "to see," like a scope or a telescope. The word came into Latin as episcopus and then into English as piscop. The "p" turned into a "b" and that gave us "biscop" or "bishop."
episkopos > episcopus > piscop > biscop > bishop
Priest comes from the Greek word presbyteros, meaning "elder" or "old man." It refers back to the ancient elders of Israel who assisted Aaron and Moses in leading the children of Israel. The word came into Latin as presbyterus and then into English as "presbyter" which was shortened to "prester," and finally "priest."
presbyteros > presbyterus > presbyter > prester > priest
Deacon comes from the Greek word diakonos, meaning "servant." The prefix "dia-" means "through" and "konos" means "common." This is someone who works by means of common duties - a servant. It came into Latin as "diaconus" and from their into English as "deacon."
I don't want to get into the debate over whether the New Testament views the office of bishop and presbyter as the same. The word is used interchangeable. But for that matter, Paul also interchanges the words "apostle" and "deacon" - that doesn't mean that each term refers to the same office. Rather the terms are fluid, but the offices are not.
In the New Testament we see three clear offices:
When the Apostles died, the terms changed, but the hierarchy remained:
Saint Paul, pray for us.