I am a history teacher and was talking with a co-worker today about art history. She said to me that pre-Renaissance art was not depicted in a realistic way because there was a belief at the time that depicting the world realistically in art was seen as anti-christian.

Basically the logic goes something like, "if we depict the world as it is we are trying to be like God and that's not our place".

My understanding of the shift of art from the middle ages to the Renaissance has been that there were developments in painting practices/technologies that enabled more realistic painting. (For example the inclusion of 3 point perspective)

My question is, to what extent was the "unrealistic" art of the middle ages a result of religious ideas vs the development of new artistic techniques or "technologies"?