The first is the Crusade. The pain caused by the war and the rediscovery of Greek civilization (preserved in Arabic in the Middle East) make people doubt the authority of Catholicism and the correctness of its theory. Then came the Black Death, which seriously weakened the religious power, led to the collapse of the traditional social structure, and at the same time made people think more about life. These two factors, together with the budding of capitalism along the Mediterranean coast (an inevitable event), led to the Renaissance. It is self-evident that the Renaissance and the subsequent geographical discoveries had an impact on the theoretical basis of religious theology in medieval Europe.

Taken together, the above points are factors that fundamentally shake religious theology.