This paper traces the exploration of religious essence by western scholars from ancient Greece and Rome to the 20th century. It is believed that from ancient Greece, Rome to the Middle Ages, they focused on expounding and demonstrating the essence of God. 16 to 18 centuries laid the ideological and methodological foundation for the exploration of religious essence. In the19th century, different academic schools explored the essence of religion from different angles. In the 20th century, due to the diversity of research methods, the understanding of the essence of religion has been deepened. Key words: the essence of western religions is multi-faceted, and pluralistic religions, as a complex social and cultural phenomenon, will be related to the definition of their essence whether they are comprehensively studied from the perspectives of philosophy, sociology, anthropology, psychology and phenomenology. However, due to the different positions, viewpoints and methods of researchers, the discussion on the essence of religion presents a diversified trend. In addition, religion is a dynamic social and cultural phenomenon, which is always associated with a specific era. Therefore, it is extremely difficult to give an appropriate and universal definition, which is still pending. Scholars' exploration of the essence of religion constitutes the pulse of religious research. 1. Elaboration and demonstration of the nature of God From ancient Greece and Rome to the end of the Middle Ages, before the birth of Christianity, some thinkers and people of insight in ancient Greece and Rome began to think rationally and discuss the problems of religion itself academically. The essence and origin of religion or god have puzzled and attracted many scholars, thus forming the basic theoretical problems of religion. The focus of this period is to explore and show the essence of God. At the beginning of ancient Greek philosophy, philosophy gradually deviated from religious myths. They criticized the traditional religion of ancient Greece and began to turn the god of religion into the god of reason. According to the fact that Ethiopians and Thracians have different gods, Sanofini concluded that God did not create man, but man created God in his own image. Democritus denied the theory of God's creation with his atomism, thinking that everything is made up of atoms, including God. He believes that people are afraid of the unknowable nature and rulers, and they want to restrain people's behavior to create God. After the 4th century BC, traditional religion and morality declined, eastern mysticism and religious superstition spread widely in Greek society, and the idea of immortality filled the whole Greek society, causing thinkers to reflect. Epicurus opposed the immortal and blind belief of the soul. He believes that religion comes from the fear of God and death, and only by relying on wisdom can we get rid of this fear. Through the analysis of different gods in Greek mythology, Proteus came to the conclusion that the concept of god was conceived by people to express their gratitude and reverence for nature beneficial to human life. At the end of 5th century BC, Chretien believed that ancient legislators or ruling classes invented God to restrain people's criminal activities, and God was a symbol of morality. Aristotle believed that religious myths originated from the confusion and surprise of nature and astronomical phenomena, and made a philosophical and rational "argument" on the existence of God, which provided a rational basis for medieval theology. It can be seen that the enlightenment thinkers in this period looked for the essence of God from the perspective of human beings, and thought that human beings created God instead of God. God is just an illusion of people's ideas, created to comfort mankind because of fear, reverence, confusion or flattery of the unknown world. Here, religion is essentially a belief in God. Their thoughts undoubtedly inspired future generations to explore the essence of religion. The Middle Ages was a period of monopoly of Christian theology, and people demonstrated the essence of God from different angles. Augustine, for example, recorded and described the course of his will in Confessions, indicating that belief in God can be sought from external things, which is an internal certainty. Thomas Aquinas put forward the famous "cosmological proof of the existence of God" in The Complete Book of Theology, and demonstrated the essence and personality of God. They all believe that faith is the foundation of religion and reason should serve faith. Therefore, the religious theory and religious theory in this period can only be religious belief and theology itself. This history actually determines the content and development direction of western religious theory since then. 2. From16 to 18 centuries, it laid a foundation for exploring the essence of religion in terms of methods and ideas. /kloc-although the religious reformers in the 0 th and 6 th centuries opposed orthodox Christianity, they still showed great respect for the word of God, and they judged everything with the word of God as the absolute authority. As Marx said: "He (Martin Luther) liberated people from external religions, but he turned religion into people's inner world." "He broke his faith in authority, but he restored the authority of his faith." (2) Although various thoughts based on humanism advocate people-oriented and rationality as authority, they still can't get rid of the shadow of God. Hobbes, Hume and Descartes are all representatives. Hobbes criticized Christian theology and its apocalypse theory, arguing that the apocalypse cannot be confirmed by the direct experience of believers, and that people should judge everything the church and the Bible say through sensory experience and reason. Hume in Britain criticized various religious theories and the harm of religious superstition with his philosophy of human nature and empiricism. However, he used skepticism and agnosticism as weapons to prove the existence and attributes of God in theory. He believed that there was no doubt about the existence of God and advocated the establishment of a "real" religion that was beneficial to society. He thinks that "Zhen/Zhexuqita/060529/11184355.html"