This may be a bit tricky, but I have faith in us.
I heard it being played by a small orchestra at a church so I don’t have any lyrics.
All I can say that the way the melody fell and then rose(raised?) it reminded me of the song The Streets of Laredo.
I’ll see if my wife remembers anything more and hopefully be back with more info.
I think you’re referring to the British version of O Little Town of Bethlehem, which differs considerably from the American version. If you’ve seen the Mr. Bean Christmas Special, it’s the carol the kids are singing just before he slams the door shut on them, IIRC.
I’m pretty sure that’s it.
That would be it!
Wow, that was a lot quicker than I thought it would be.
Thanks!
Beautiful hymn. I don’t think I’ve ever heard it before! 
I have a recording of Pavarotti singing it in Italian. Now, of course, it’ll always remind me of The Streets of Laredo.