If your not a good christian you might not know what these persons actually do in the church and even those who are good Christians don’t know the actual meaning of these words. The word Reverend first appeared in the 17th century England and it comes from the Latin word “reverendus“, it means someone or something “worthy of respect.” Pastor is the Latin word for shepherd, which is how Jesus himself referred himself. Shepherding was a very popular job in that era, like many last names that were associated to jobs, Pastor is one of them. Parson is not widely used like the others, because it comes from more of a local background. It appeared in North England at first, where the town’s priest knew how to write and read so they called him the town person. If you’ve ever been to the north part of England, you might need the explanation how person became parson.
Also another reason why pastors in North England are called Parsons is, because Parish Churches originated there. Even now they’re an important part of the communities in Northern England.