The Holy Bible was supposed to be read by laymen and was supposed to be kept under lock and key. This process helped the clergy to mislead the people of the doctrine. Thus, the clergy was keen to keep the supremacy and many truths were hidden from the church members. The pope kept ‘the need to know basis’ principle religiously. Dr. Martin Luther, a priest himself, was the one revolted against the papal supremacy.
But by then, the power of church and Pope was significantly reduced by the crusaders. The crusades King made that the Lords and knights dispose of their movable and immovable properties to regain lost power and to fight. The Western Europe experienced something else. They exchanged a gadget, compass, ship designs, dagger or gunpowder in a barter deal for silk, tobacco, cotton, sugar, and spices.
The spread of academics including numbers, chemistry, algebra, astrology also was going on rapidly. The Chinese influx and Silk routes were also responsible for the erosion of Church supremacy. The invention of paper, ink and printing soon came into daily life. The metal came as an undisputed boom for industrial revolution. Food pattern also changed with salt as a luxury intake.
The church could not stop the growth of cities. Civilization and knowledge was spreading faster to the dislike of the Church. The living standards were going up with new inputs into agriculture, trade, and finance.
As a logical course, new concept of universality between different cultures –Muslim and Byzantine- took shape losing the grip of the Church substantially. The ox was replaced by horse. People could think independently. The strictures on clothes imposed by the church were bypassed deliberately. The banks came up and the economic fronts were showing changes.
Thus, the grip of church was loosened. And people gathered courage to criticize Pope even which was the death bell for the church supremacy.