As I stated previously, the Cyberhymnal is pretty clear on the history of this hymn: How Tedious (Midi provided of Bach's melody).

The hymn was published in "Olney Hymns," London, W. Oliver, 1779. It was set, by Lewis Edson, 1782, in the "Choristers Companion," New Haven, CT, 1782, to the music of the section called "Greenfields" (applied by later writers, not Bach) of Cantata 212, "Mir Hahn en Neue Oberkeet," (commonly called "The Peasant Cantata") composed by Johann Sebastian Bach.

The questions remaining are: 1. Did Bach borrow and rearrange folk or other music for his cantata? 2. I don't believe Newton is cited clearly as the author of the lyrics of "How Tedious...." in "Olney Hymns."

I will attempt to get a translation of Bach's Cantata 212 (which is a church choral work as well, but structured, much longer, and "boisterous" according to some reviewers.