The right to appoint the priest was an important privilege commonly known as an advowson. Advowsons could be bought and sold and were therefore very important possessions, for with the advowson went the entitlement to the tithe. In the Middle Ages, advowsons accumulated in the hands of the great abbeys and monasteries and thereby contributed to the renowned wealth of those institutions. It follows that in many instances the tithes of a parish became due to an individual or agency rather remote from the parish of origin. As the Middle Ages progressed, the tithe underwent a series of subdivisions and classifications, some of which will be discussed later. The value of tithes to those who acquired them (mainly by the purchase of advowsons) led to changes in the rank and privilege of the parish priest.

The person or agency to whom the tithe was payable became known as the Rector; but as rectors were often remote from the parishes a new deputy or vicar was appointed to act as the parish priest. The vicar was not entitled to the tithe although it was usual to provide him with a third of the total tithe of the parish as a basis for a living. It can be appreciated that the difference in income between the rector and the vicar could be quite considerable, with the bulk of the tithe income going to an often absentee rector. Dissatisfaction with the tithe was compounded by the fact that, with the trading of the advowsons, the rector need not have any connection with the church at all.