I first heard it sung by the Scottish group, Sangsters, many moons ago, and then sought out the words and found the various versions Maddy Prior recorded. (And yes, Rick Kemp was correctly attributed as composer.) Maddy's earlier version was in a higher key than the later one.
A friend suggested that we mix it with "Da Slockit Light", lovely fiddle tune by Tom Anderson, and that works pretty well, using part of it as an instrumental break. The song and the tune have the common theme of "guiding light" after all.