SOPP577: Serving at the organ to lead a congregation of untrained singers

This question was sent by Steven, and he writes: “Hi Vidas, Not long ago Vidas it was my job to serve at the organ to lead a congregation of mostly untrained singers in a meeting outside a worship service with the singing of a closing song with which most of them were unfamiliar. The tune was St. Clement, a traditional hymn not especially easy for a trained voice to sing that's better known to members of the Anglican faith and perhaps a Methodist or two in the audience but completely unfamiliar to everyone else. This number does not appear in any of the newer hymnals -- I have only found it included in a couple of very old editions of hymn books which have been out of print for a very long time. People singing this tune on YouTube videos are doing so at a tempo Moderato about half the time and the other half of the time they sing at something close to an Adagio."