Have you heard of Maimonides, aka The Rambam, aka Rabbi Moshe ben Maimon?
He was a Torah scholar, Saladin's doctor, wrote widely on mysticism and rationalism, and was super controversial.
He lived in Spain. Here's a common rendering:
He was born in 1138. He wrote The Guide for the Perplexed. In the late 1100s, controversy erupted over the fact that he had the gall to suggest that Torah scholars should work rather than live off of benefactors, and that his Mishneh Torah was more helpful than many rabbis.
The Guide for the Perplexed attempts to reconcile science and philosophy with rabbinic Judaism. This is no small thing! Assimilation in Spain and France was rampant among Jews, and many were not happy about this work, to put it lightly.
So the author of the book I posted, Shaarei Teshuvah, is Rabbi Yonah of Gerona. He is born in 1180. Unlike Maimonides, he spent all day learning Torah. He is related (by blood and marriage) to the Ramban, aka, Nachmanides, aka Rabbi Moses ben Nahman.
(Maimonides dies in 1204.)
Ramban (not to be confused with Rambam) is a mysticist, not a rationalist. If you've read his commentaries, he is very sassy, to put it lightly.
So back to Rabbi Yonah. Many rabbis believe secular education can lead to assimilation. Reading Maimonides might constitute this!
Assimilation is rampant in France and Spain. A way of life is at stake. This is no small matter!
So in 1232, Rabbi Yonah, his rabbi, and others announce a ban on reading Maimonides!
The Jews are bitterly divided, for and against. Ramban tries to mediate, to no avail.
Remember, this is 1232. The crusades are raging. After centuries of good relations and flourishing Jewish mysticism under Muslim rule, Christian influence is literally deadly to Muslims and Jews. The stakes are high!
Maimonides ideas not only challenged Jewish orthodoxies, but Christian ones. The Dominicans noticed. They confiscated works of Maimonides and burned them in the streets of Paris — along with many other sacred Talmudic books — for good measure.
Rabbi Yonah quickly realized he had made a huge mistake. But he did not just shrug it off (I mean, how could you?!).
He pledged to travel around the Jewish world begging for forgiveness, hoping to end at Maimonides' grave in Israel, where he would ask him for forgiveness.
He didn't ever make it to Israel to fully atone. But until his death three decades later, he taught in Yeshiva and wrote book upon book about the hard work of repentance.
Shaarei Teshuvah, Gates of Repentance, the image I posted, is one such book.