We may suppose that very often a single god out of the many became a special object of worship to a single nation, either as a local deity supposed to have special power over their fortunes, or as the chief among all the gods. This god is naturally propitiated by every form of worship and title of praise which the people think will please him. No flattery is too gross and no attribute of goodness or power too great to be bestowed upon him. The limited deity is thus gradually promoted to omnipotence, omniscience, and perfect goodness. The Virgin Mary among Catholics and Jupiter among the Romans are patent examples of this process, according to Hume. Even after bestowing these magnificent appellations upon their deities, the mass of men are so ignorant of the rational meaning of the terms employed that they seek to gain the favor of their gods by practices which would disgust even an intelligent and cultured man.
History shows that these two chief forms of religion have a flux and reflux in the human mind, and that men have a tendency to rise from polytheism to theism and to sink back again into polytheism. The attributes ascribed to the single deity are too high to be retained long in their purity. Such a Being appeals neither to the comprehension nor to the affection of men, and He is soon surrounded with a court of intermediary powers which are the chief objects of devotion among men and hence tend to usurp the chief attributes of the Almighty. Pure monotheism thus soon degenerates into polytheism, which, in turn, destroys itself and turns the tide back toward monotheism.
It is not necessary to dwell upon the obvious philosophical criticisms to which The Natural History of Religion is open. Its strength lies mainly in the fact that it is the first important attempt to give the origin of religion a scientific treatment apart from a bias in favor of supposed Biblical revelation. Its obvious weakness is its complete divorce of the passions from reason, which leaves the history of religion without meaning in the development of truth. It is clear that Hume's purpose is not primarily to give a real history of religion, but rather a psychological or anthropological account of its origin from the constitution of human nature. Religion is regarded not as a miraculous gift from Heaven
