Aristotle being applied to Christianity wasn’t new in the 11th and 12th centuries (although applying Plato or the Stoics was much more popular in early Christianity). You get Aristotle-ish bits in St. Irenaeus, for example, and many early Christian writers were big on Christians studying natural philosophy in order to better understand God’s glory expressed through His Creation.
What was new was that it was being applied a new generation of Christians – by medieval people who hadn’t had the libraries to study Aristotle before. (Medieval Europe knew who Aristotle was, but they mostly didn’t have his books, because anybody in early Christian times who wanted to study Aristotle would have read him in Greek.) The condemnations largely stemmed from bad/remote translations that went from Greek into Arabic into Latin, and often included lots of commentary by the Arabic-speaking translators/scholars; so the first work of the Scholastics was either to get direct translations from the Greeks, learn Greek and get Greek manuscripts and then read the original (not possible for most folks in Western Europe because of Muslims blocking trade routes, although some worked on it, particularly in Spain and eastern Europe) or to filter out the Muslim bits from Muslim translators. The other big issue was the people who loved Aristotle so much that they were ready to go all pagan-universe and ignore known medieval science facts just because Aristotle had said so, which was sorta stupid.
So great Aristotle teachers like St. Albert the Great had a lot of sorting to do, in order to use Aristotle’s good parts and ignore his bad parts. They ended up teaching people to do this with all sorts of pagan and Muslim sources, and teaching them also to pay attention to their own experience of how the world worked, as well as to the authority of these writers.
“Experience” could be sought through going out on purpose and trying things out to get “experimentum”, which is how we got experimental science.
So you get writers like St. Albert saying things about how Aristotle said this and Averroes said that about antlions, and Pliny said this other thing, but personally, I used to keep antlions as pets and play with them, and I saw them eat X and Y and do Z without any problem whatsoever. And I’ve been all over Europe and the antlions do the same thing there. So it’s possible that they had different kinds of antlions around where Aristotle and Averroes and Pliny lived, or in their time, but it’s certainly not true of our antlions around here, today.
So yeah, mostly what was new was the excitement and interesting things you turn up when you look at sources you’ve only heard about before, and you examine them with fresh ideas. It wasn’t the first time Christians played with Aristotle, but only a “modern” time when it happened.
