There's always 2 sides to a story. It would be interesting to get the teacher's side of this. What prompted him to say this? Poor humor? Ideology? Hopefully we get answers to that.
Overall, I think this remark needs to be put in context with the entire exchange instead playing up the incendiary parts of it that cause folks to go into apoplectic rage sessions.
What harmless context would it be in that would prompt the student to ask who the **** the teacher was talking to?
Who said anything about it being "harmless"?
I just prefer to hear everything before I opine on topics like this. So far we've only gotten the kid's side of the story. I would like to hear the teacher's. This would provide context and better understanding of what transpired.
No idea where "harmless" came from.