**You avoided answering my question about supersession,
but here you show that you do in fact think of Judaism as belonging to Christianity. I'll just say that this seems to me historically bizarre and lazy thinking.**
I thpoght he had said he was not familiar with the term supersession. You act as if you've caught him in some lie, but do not forget the old saying, "to a fly caught in horseradish, all the world is horseradish." It makes perfect sense to me that people who hold beliefs that fall within the meaning of supercession might be unfamiliar with the term.
Also, what do you mean by "historically bizarre and lazy thinking"? A believing Christian surely is permitted to profess belief that Christ came for all mankind, "to the Jew first but also to the Gentile", as Scripture puts it. To call that lazy or bizzare is to apply those terms to a fundamental tenant of someone's faith. You're free to think that way, and of course to express yourself, but you should not be surprised if there are those who find *your* views at least as offensive as those you object to (and no more On Topic.)