For one, an almost universally overlooked bit of history is how absolutely crucial muslim scholars were in preserving classical texts, in keeping an unbroken chain from the Classical Age until the Renaissance. Places like Al-Andalus -- muslim Iberia that is -- or Bagdhad, were the centres of knowledge in the world in their time, and also places of surprisingly high religious tolerance, where Christian, Jewish, and Muslim scholars studied and discussed together. Many translators and schools of translators were founded and supported, and that's the path countless Greek and Roman tomes took until our days: translated to Arabic, later "rediscovered" by the West.
Among Christian monks, on the other hand, for centuries starting around 300-400CE the highest goal was asceticism, one of the corolaries of which was that one should waste no time studying or preserving pagan texts or indeed anything which were not: prayer books, missals, homilies, responsories, etc. An innumerable amount of works were lost during the centuries where Christian monasticism was most active. If indeed the monks preserved that ancient, pagan knowledge, then how can this be?
Not to mention the fact that Christians post-Constantine and Theodosious were engaged in brutal and relentless persecution and suppression of non-Christians, so called "pagans", and pagan art, pagan temples, pagan beliefs, and of course, pagan literature. They burned temples and all the art therein, they burned libraries, they suppressed academies and professors, either by force or by ending the state's patronage,
This paper is a great read, admittedly biased in its sources but not misleading (it cites contemporary opponents, rather than christians): https://www.jstor.org/stable/pdf/27899562.pdf
I think its somewhat inevitable that pagan works would be lost over the centuries, and less surprising that they would survive in dryer climates. Ultimately, I think to make the christians look particularly oppresive and destructive one has to overlook a lot of pagan violence. In the case of the islamic world, we can say for sure that there was a general destruction of churches, existing infrastructure and a general looting of most of the areas that came under islamic domination. And this is the pattern for the exchange of cultures nothing unusual. Taking the Dome of the Rock for an illustrative example - the Mosque at the dome of the rock began as a looted Marian shrine, built over the ancient roman temple which the romans themselves built over Herod's second temple.
Tier 1 (most intolerant): Suppress the out-group vigorously, including executions, torture, secret police, interrogations, etc.
Tier 2: Suppress the out-group violently (executions) any time they're noisy, but don't seek them out.
Tier 3: Disfavour the out-group, without permitting conversion.
Tier 4: Disfavour the out-group, permitting them to convert.
Tier 5: Disfavour the out-group socially and informally, but not in matters of enforced law.
Tier 6 (most tolerant): It's illegal to disfavour the out-group.
The reason I mention this is that modern notions of religious tolerance target maximum tolerance (Tier 6 or whatever), but there's a lot of variety through history. For example, I think that persecution of Jews under the Romans was, in some cases, only because the Jews were unwilling to also in-form-only obey the dictates of Roman religion (2nd Commandment makes that tricky). Contrast that with Nazi persecution of Jews, which was much more aggressive about seeking them out. It's worth it to identify that one of those is more tolerant than the other, even if we wish for our society to be more tolerant than either of those.
In that context, my understanding is that the Muslim law of the medieval period is pretty clear about tolerance, and that both Al-Andalus and Baghdad followed these rules. "People of the Book", i.e. non-Muslim monotheists, were granted a large set of very specific protections, while still being treated less well than Muslims. (Note that non-monotheists were not granted protections; I imagine that this did not result in much religious tolerance towards those people, but that's just a cynical guess.) These specific protections were strong enough that it made sense for non-conformist scholars (Christian or Jew, as long as they were monotheist) to migrate from Christendom to Dar al-Islam. Compared to modern west-coast notions of religious tolerance, this isn't great. But it's still remarkable and praiseworthy, especially in contrast with modern Sharia, and in contrast with then-contemporary Christian kingdoms.
In summary: it's not that medieval Muslim states were tolerant by modern humanist standards. It's that they were more tolerant than modern Sharia Muslim states, and more tolerant than medieval Christian states.
The importance of Ancient Greek literature in the Byzantine Empire is readily evident from things like Homer remaining a cornerstone of Byzantine education all the way through the first millennium, and Christian polemicists starting to write in Attic Greek instead of the Koine.
If you want to see just how much of the Greek tradition was preserved in the Christian world, and not the Muslim world, simply visit the Classical Philology section of any university library and look at the manuscript sources (including, yes, monastery copies) of any Oxford Classical Texts or Bibliotheca Teubneriana edition of Greek writers.
The Muslim centers are not only preserving ancient Greek learning and books, they are cherishing and enriching them for several hundreds years [1]. To them these ancient Greek books are equivalent of modern days da Vinci's paintings that can be weight in gold, literally no kidding. At the time, if you are doing translation of any Greek texts you can get paid by the weight of the translation in gold equivalent! Please tell me at any other time this is happening in any part of human history or even now.
It's also reported that at one time, Abbasid Caliph Al-Ma'mun was demanding an original copy of the Ptolemy's Almagest book as the condition of a truce between Byzantine Empire and the Abbasid Empire. This is really something big because based on the saying of Muhammad that prophesizes any Muslim leader who can defeated and conquered Byzantine Empire (Constantinople) is the best leader ever. He basically abandoning this potential privilege title because of an original copy of Ptolemy's book. If you think he is too weak to defeat Byzantine and resorting to lame truce, please think again. He basically conquered and subjugated entire modern day Afghanistan for good, and only a few legendary leaders that even managed to do that including your beloved Alexander the Great. For the record, the mighty British Empire and USA did not manage to do just that.
Al-Ma'mun is also the founder of the "House of Wisdom" where Al-Khwarizmi was the first director of the center and his name is very familiar because apparently the "algebra" and "algorithm" words were derived from his book title and his names, respectively. Because of his contribution to science one crater in the moon (Almanon) is named after him[2].
Believe it or not, according to some of modern historians, the extreme love for knowledge of the Abbasid Empire was partly blamed on the downfall of the Abbasid Empire at the expense of Islamic spirituality. This perhaps mainly due to the Islamic teaching that says after you're dead there are only three things that can increase you deeds in the hereafter. Firstly your God fearing children, secondly your donated and lively wealth for charity (waqaf) and thirdly your contributions to the knowledge that are beneficial to other people.
[1]How Modern Science Came Into The World, https://www.jstor.org/stable/j.ctt45kddd
I am thankful we the works saved by Muslims, but there has been a gross over reaction where the true source of most of our knowledge of the classical world has been ignored so people can score woke points for praising non western cultures and erasing the contributions of the west and christendom.
Again, go look at the manuscript sources for all those OCT and Teubner editions.
Just for the sake of arguments, even if the Cristian world have most of their copies, are having the back up copies by the Muslim world really help preserving the books when there was no Google Drive around?
At least we probably can agree that these Muslim scholars were not only appreciating but they were also cherishing the Greek books just like we are cherishing the PlayStation 5 not only appreciating it. For them it is part of their religious duty to contribute and spread the knowledge regardless they were from India, China or Greek. You need to understand that these scholars not only preserved the book but they cherished them. It's given fact that you only keep what you value and cherish, and by nature human are selective hoarders. Without the ransack of Baghdad by the Mongol where the rivers turned blue/black by the ink of the thrown and demolished books it's probably not an exaggeration to say that we probably living in Mars by now. The fact that the lesser backup copies in Toledo, Spain that fell into the European hands essentially initiated the knowledge revolutions or renaissance as they called it today.
[1]https://www.americamagazine.org/faith/2019/12/27/these-are-m...
While you might be very proud that the Muslim world preserved (a very few) Greek and Latin sources that were also held by the Christian world, that is irrelevant to the discussion launched by the OP.
Even Columba Stewart would agree, like the rest of scholars engaged in matters of textual transmission, that the great majority of Latin and Greek writers that have come down to us today, came down through manuscript traditions in the Christian world, and the Muslim world has contributed only in a few cases.
Of all people, the Christian Coptic Pope is the culprit who ordered the demolition of the great library in the 4th century CE. The Muslim Empire and scholars somehow managed to scrambled majority of the Greek civilization learning and books of what have been left after the destruction, and also significantly add their own knowledge contributions. The effort resulted in the two greatest centers of ancient texts in the world by the 11th century CE.
Baghdad center was ransacked to the ashes, and majority of the stored books and manuscripts demolished. The only surviving secondary or lesser center of the two was Toledo. Toledo fell to the Spaniard in 11th century. Benedict the abbot who in charged of more than 600 monastery has ordered the clergy to literally copy and also translate books and scriptures from the center in Toledo. In Toledo there existed original Arabic books on the new knowledge, Arabic translations of Greek books and scriptures that otherwise have been lost forever, and perhaps many copies of the original books of Greek civilization but we probably never knew the exact composition since this happened about a thousand years back. These copies of the books and manuscripts were ordered to be kept in these many monasteries, and the books and manuscripts remained there for centuries. If you think only a few works (less than five) of the ancient Greek works that were preserved during the time due to the Muslim empire and scholars efforts, I really want to know what are the things that you are smoking at the moment?
With regard to Toledo, you appear to have read some pop-sci articles about it that made you excited, but you overestimate its impact. We know the provenance of the manuscripts of the Greek and Latin writers that have come down to us, and Toledo played absolutely no role in the transmission of most of them. Again, Greek and Latin manuscript studies is a well-established field.
Finally, none of what you have been posting is relevant to this subthread, and if you really want foreigners to appreciate the erudition of the Muslim world, getting your information right is important. With your carelessness about the facts, you are only damaging your own cause.
The Christian establishment in the antiquity and the middle age were so anti-knowledge that it was the opposite of Muslim empire at the time. The anti-knowledge behavior has been exposed by movement such as Renaissance (technology) and Protestant (religion). Do you know that by law at the time you cannot translate Bible to other local languages in many part of Europe until a few centuries back? Yes, that is the main reason you have the Protestant movement.
Regarding the effect the Toledo it is mentioned in the article by your own foremost Greek learning and manuscript expert in the so called pop science articles by Dr Columba Stewart and also other similar experts. It seems that you denied most if their relevant claims regarding Toledo. If you don't mind can you please tell me what is your credentials and expertises in Greek learning history that you have disagreed with most of these reputable scholars regarding the matter?
Anyway in Arabic the non-believers are referred to as "kafir", literally means the "denial of the truth".