Each of the lyrics comes from an old-time hickory song for fiddles, and is a lyric from that corresponding song.

"Fire on the Mountain" --> "Fire on the Mountain, run boys run"

Fire On The Mountain - Fiddle Player POV

"The House of the Rising Sun" --> "The Devil's in the house of the rising sun"

House of the Rising Sun

"Ida Red" --> "Chicken in the bread pan peckin' out dough"

Ida Red - Bob Wills & His Texas Playboys

"Granny Will Your Dog Bite" --> "Granny does your dog bite? 'No child, no'."

FTC #149 Granny Will Your Dog Bite

And for your furthered education, The Mountain Whipporwill.

in a time before things like radios and record players, every time you heard music was because there was somebody in the room with you playing an instrument. and many, many, many social events involved dancing, which requires music. so, if you're planning any kind of gathering in the american south or appalachia, you need to find a fiddler. and the fiddler's job is to play music that everybody knows and likes and can dance to.

the mistake The Devil makes in his bet with Johnny is that he misinterprets the contest as being about technical ability, so he has this big flashy song. he plays fast and impressively with a band of demons playing unfamiliar instruments in unfamiliar rhythms. he's definitely more skilled at playing than Johnny, and thinks he has it in the bag.