Larry Siedentop

“Christianity changed the ground of human identity. It was able to do that because of the way it combined Jewish monotheism with an abstract universal that had roots in later Greek philosophy. By emphasizing the moral equality of humans, quite apart from any social roles they might occupy, Christianity chagned "the name of the game". Social rules became secondary. They followed and, in a crucial sense, had to be understood as subordinate to a God-given human identity, something all humans share equally. Thus, humans were to live in "two cities" at the same time.”
― Larry Siedentop, Inventing the Individual: The Origins of Western Liberalism

“Christianity took humanity as a species in itself and sought to convert it into a species for itself. Thus, the defining characteristic of Christianity was its universalism. It aimed to create a single human society, a society composed, that is, of individuals rather than tribes, clans or castes. The fundamental relationship between the individual and his or her God provides the crucial test, in Christianity, of what really maters. It is, by definition, a test which applies to all equally. Hence the deep individualism of Christianity was simply the reverse side of its universalism. The Christian conception of God became the means of creating the brotherhood of man, of bringing to self-consciousness the human species, by leading each of its members to see him- or herself as having, at least potentially, a relationship with the deepest reality - viz., God - that both required and justified the equal moral standing of all humans.”
― Larry Siedentop, Democracy in Europe