[Morality Games]

What society in the past ages was a nice place to live?

Few or none, but that just demonstrates the non-exceptionalism of Christianity in practice. Functionally, it amounts to much the same thing any other religion.

Portions of Italy were once among the most enlightened regions for learning after the dark ages, all under the sphere of the roman catholic church. You'd have to have a fairly well off and accepting society to allow a painting called "School of Athens" to be done right inside the Vatican.

I'm not sure which era exactly you are talking about, but if we are talking about the Renaissance, only the upper classes were acccepting, and their acceptance was never unconditional. Genuine acceptance posits no or only a few stipulations. Moreover, many of the artists and their patrons went rogue, abandoning Christianity in favor of pantheism, deism, and atheism. That they were 'accepted' derives largely from the fact they didn't go into detail about the content of their beliefs outside a few very exclusive channels -- however, everyone can enjoy a work of art, be the maker religious or non-religious. That they produced marvelous works of architecture, literature, sculpture, and art played a large role in a lack of rigorous investigations in the piety of many nobles, merchants, and artists. However, in such instances where a lack of piety was found (if someone upset the wrong clergymen), the outcome was rarely nice.

In particular, there is nothing accepting about a portrait called, "The School of Athens," because Platonism was a steady influence on the growth of early Christianity -- not hard to accept people whose ideas you agree with.