I stumbled across this thread as I have been listening to Doc Watson's 1964 Vanguard recording of this song. I first heard a friend of mine singing this busking on the street in the 1980s. He may have mentioned John Renbourn as the source. In the liner notes of the Doc Watson recording written by Ralph Rinzler of Deep Gap N.C. in 1964, Doc remembers his Granny Lottie singing it, probably from the "Southern Harmony" hymnal that would have also provided a shape note harmony setting.