At the end of Isaac Bashevis Singer's short story "The Primper", there's a small anecdote about a young man who studied the Rambam / Maimonides until he became an unbeliever:
In Rovna there was a young scholar who studied Maimonides so much, he became an unbeliever. They nicknamed him Moshka Maimonides. He knew all of Maimonides by heart. Saturday he would sit by the window with a cigarette in his mouth and recite Maimonides.
(translated by the author and Ruth Schachner Finkel)
Why would the young man have become an unbeliever because of studying Maimonides? Maimonides was a Jewish scholar who wrote out all of the laws and principles of belief, among many other things; why would reading this lead to becoming an unbeliever?