Fuedalism
In order to understand the context of the Reformation, it is important to understand the how society was structure. The structure was called feudalism.
The King owned the land. He would give land to subordinates in exchange for resources like food and soldiers. The king gave land to Nobles in return for money and knights. The Nobles gave land to Knights in return for protection and military service. The Knights gave land to the peasants in exchange for food and services.
This system helped to provide what was needed to those who needed it. This worked fine until something happened to unbalance the system . . . like a drought or famine. In a just system, the king, nobles, and knights would not demand their portion during those hard times. However, the system was seldom just. The peasants would starve, so that the higher ups could have their portion. This created a volatile climate of suffering for the poor and indulgence for the rich in which the Reformation began its revolution of the church and society.