Oh, My Professor

(It is the first day of class. My classmates and I are unsure of how to address the professor.)

Me: “Sir, what do you prefer to be called? Professor [Last Name]?”

Professor: “No! That’s way too formal to me, and I won’t answer if you say it. You can just call me [First Name].” *pauses for a moment* “Or you can call me God. I respond to that, too.”