Funny thing about the plural first person pronouns (we/us/our): it can mean several different things:

1. Me and them

2. Me and you

3. Me and you and them

Your comment makes sense if GP meant 2 or 3, but if GP meant 1 then you're each saying the same thing (well, if you'll let your version be a plural second person, anyhow).

That's not what Christians believe. I've had Muslim friends who prayed for me when I had tough times and I didn't complain because I didn't practice their religion. It's the thought that counts. I think you focus on that part instead of the fact that somebody wishing happiness on you, probably from some existing resentment of Christians.