Maybe it is "sacred" in that it is one of the "old" standards of bluegrass, and therefore must be revered.

You know, like in journalistic circles where a "sacred cow" is an advertiser about whom nothing derogatory may be printed (please[!] no attacks about use of the term -- I didn't make it up).

Does the "introduction" sound a bit sarcastic? Does to me if they actually used the term "neighbors."