Were I still going to school, though, I'd probably have stayed in the class and made him try to prove that Christianity, like the other religions, is not also a false religion. I'd probably cause him to offer to pay me not to attend his classes.
But, in those days, I had other things to do, so I settled for blowing him off and complaining to the administration about a proselytizing professor at a state-funded school. That took less time and energy. In those days, I had not learned patience as thoroughly as I did later.
I had one other class that was taught by an incompetent professor, but this time in my own major. It was a "Dramatic Literature" 300-series course. I did not withdraw from it, because my future wife-to-be had caught my eye as a fellow classmate in that course. So, I stayed. The class, which was supposed to look at plays not written by Shakespeare as literature, of course. Instead, the lectures were a tedious recounting of various productions of the plays we were studying that the professor had attended in different cities, often with a blow-by-blow description of after-parties with the cast.
In one notable class session, the professor described her chagrin at appearing at such a party, only to discover that a player was wearing the exact same outfit as the professor. That, apparently, spoiled the entire event for her. We never did discuss drama and the structure of it during the classes.
I wrote another letter regarding that professor, who was not there the next semester. I'm a very convincing letter-writer, it seems.