I remember listening to the radio in the car one day years ago, hearing a flute playing unfamiliar Christmas music and thinking that it sounded an awful lot like Jethro Tull. I couldn't imagine that Jethro Tull would have a Christmas CD. But they do. You can read the lyrics at the band's site. You can listen to some of the music here. I like this one, but The Husband's not a fan.
A Christmas Song: