yanbu - if this is workplace bullying which I agree it sounds like, taking into account your previous posts. I think he may have just shot himself in the foot.
He has asked you to stay later than your normal time on Christmas eve, possibly thinking that he can use this as an example of your lack of commitment or whatever. I urge you to take it to someone higher, as to me it is an extreme example of his unreasonable demands. Good luck and don't go, re-schedule for before this date