Rectors and Vicars
What's the difference?
Why is the incumbent of St Peter's called Rector and the incumbent of St Mary's called Vicar? The answer is simply - money! As the parish system developed in England, a method of paying the clergy evolved. This was done through tithes, the payment of a tenth part of all the produce of lands of the parish. Often the Lord of the Manor endowed land to the church from which the priest could also derive an income. This was the parson's glebe. The clergyman who was appointed to the parish and entitled to the tithes was called the Rector. The word itself comes from the Latin regere meaning to guide, lead straight, rule or govern.
Now some lands were more productive and extensive than others, so inevitably some parishes were worth more to the clergy than others. The ones that were rich attracted the attentions of those who were seeking an income, or to increase an already substantial income. The Lord of the Manor, be it the King or some other noble, might use his power of presentation to reward a dutiful servant or politician. As long as they were in clerical orders (and many who had been educated, were) they might expect to be presented with a well-endowed parish. Of course, they had no intention of actually living and working there! So instead they took most of the income - and appointed some poor cleric to do the job of actually taking services and ministering to the community in their place, paying him a small amount of the total entitlement. This person was their Vicar. Again this comes from the Latin word vicarius meaning a substitute. Hence we get the word vicarious meaning "in the place of". This custom led to great abuses with some powerful clergy, including many bishops, holding a number of benefices and becoming very wealthy. In 1603 a law was passed prohibiting a priest from holding two or more parishes over thirty miles apart, so requiring the clergy to reside in their parishes. We clergy are still required literally to "sign in" once a year at the Archdeacon's Visitation, to show we are not absent from our parishes.
So, put simply, a Vicar is just a substitute for the real thing, which is a Rector! One up to St Peter's, then. However, the Vicar of St Mary's might counter that - in contrast to the wealth of St Mary's - St Peter's was so poorly endowed that it wasn't worth appropriating! These titles no longer reflect the way that clergy are remunerated. Clergy stipends are paid centrally, and every incumbent - whatever the size or significance of the parish - gets paid the same stipend. The differing titles live on as a reminder of our history, and of the way the parish system of England came into being and was resourced.