Mode of Worship
Marx spoke extensively about the ideas of historical materialism and historical progression. Essentially, each mode of production for a society (slavery, feudalism, capitalism, etc.) determines the society's cultural values, organization, and other such aspects of civil life. For example, a feudal society emphasizes values like honor and glory, while a capitalist society emphasizes values like freedom and liberty.
Moreover, when a society's mode of production does not match its material conditions, the mode of production must change, either through revolution or a more gradual change. For example, due to the Roman Empire's inability to expand and gather more slaves (slavery being the mode of production for Rome), the system collapsed and over time feudalism became the mode of production for Western Europe. As another example, the material basis in France had developed to the point where feudalism was no longer a fitting mode of production, leading to the French Revolution.
This is a very brief explanation of historical materialism. There is one part I would like to expand upon, that the culture and customs of a society is determined by its mode of production. I would like to compare this to organized religion, specifically Christianity.
Rome was the dominant force of the Mediterranean, the state was all-encompassing in Roman civil life. Festivals were run by the state, not private individuals. The head of the pre-Christian Roman religion was appointed by the state. The Republic was largely run by wealthy aristocratic families, essentially a merging of the government and the rich. The Roman state was synonymous with Roman life. However, in the colonies and provinces of Rome, there was some autonomy. As long as the local authority submitted to the Roman state, paid its taxes, and supplied Rome with auxiliaries and food, Rome generally let them manage themselves.
When Christianity was first beginning to spread, how did Rome respond? First, the Roman state sought to eliminate the religion, but seeing that it could not, it instead adopted it as the state religion, mandatory for all citizens. Ecumenical councils would form to decide major points of the religion, with the emperor of Rome often calling the councils, but regional churches and bishops were fairly autonomous in running their churches. This is somewhat in parallel with the behavior of the Roman state and its provinces.
Then, when the material conditions changed, when the Roman Empire began to collapse, feudalism became the dominant mode of production and structure of society. Under feudalism, a king would run the state, create various laws and rules and so on, but the king generally derived his power from the nobility, the aristocrats. When there'd be war, the king would depend on the nobility for men and materiel. This same system was paralleled in the church. During the decline of the Roman Empire, the bishop of Rome declared himself the Pope, the head of all bishops. While the bishops did maintain some autonomy, the Pope was now the official head of the church, being able to make official decrees that all bishops had to adhere to, and so on. The Pope also could call on the various bishops for donations, or call them for support such as during the crusades.
Throughout the centuries, the system of feudalism was generally maintained. But the black plague disrupted Europe, the material conditions changed, and the system of feudalism no longer matched the material conditions of society. So instead, the force of the capitalist class shifted to dominance. Though this generally did not come out in full-swing until the industrial revolution, the capitalist class began to emerge not only from the instability of feudalism, but also through developments such as the papacy allowing the Knights Templar to 'rent' out money for a fee, circumventing the prohibition on usury. This allowed a mercantile class to flourish and grow. Now, the general spirit and ideals of capitalism are individualism, liberty, freedom, and so on. Compare this to the reformation, which began fairly soon after the decline of feudalism and the rise of the capitalist class. The reformation generally denounced the supremacy of the Papacy, denounced the institutional church, encouraged individual study of scriptures and commentaries from various theologians, and many other individual shifts in perspective. Again, these ideas that changed the mode of worship generally came from the ideas of the emergent influential class of the merchants and bankers, the capitalist class.
As even more evidence, look at the comparison to different parts of Europe, their religious and economic development. The Eastern Roman Empire did not fall at the same time as the Western Roman Empire. The Byzantines, and the region in general, did not adopt the feudal mode of production. Similarly, the mode of worship in the Eastern Roman Empire generally stuck as Eastern Orthodox, splitting from the Catholic church, not recognizing the Papal supremacy, essentially maintaining the old Roman mode of worship. As another example, Protestantism. The places where capitalism developed the most, such as Germany and England, were generally protestant. Meanwhile, the places that capitalism was slower to develop were also the places where Catholicism was the most entrenched, such as Spain and Italy.
Again, this is not saying that the mode of worship, the actual organization of the church and the ideas inside of it, determine a society's ideals, mode of production, or development. Instead, the society's mode of production and dominant class put forward structures and ideals that seem to be adopted by the church.
This is also not to say that the church's doctrine becomes compromised. While many changes in doctrine and organization do change, the churches do generally stick to the core creeds. The idea of historical materialism affecting the church is, again, more focused to the structural mode-of-worship, the institution of the church, the ideas and values that shape theology and its development. Compare it to the way feudalism or capitalism operate: there is a ruling and working class, there is a class society. The core aspect is maintained, even if other structures and values within that society change.
Overall, it is very interesting to look at the church and how it has been affected by the mode of production, dominant ideals, and societies in which the churches are established. Churches often position themselves as these immovable institutions separate from the world and its ideas, as an invariant line, but it is quite illuminating to see that the development of the church is tied quite closely to the material development of the society around the church.
This isn't necessarily a new concept; groups such as the Puritans believed in returning to a 'primitive', an original, form of Christian worship. However, the interesting part is moreso about what has caused the church and worship to change over time. Instead of some great thinker, a great man, it is simple economics and material conditions