John Moloney wrote this text based on Psalm 102. It is set to a “traditional french melody” in CWB II, but they aren’t more specific than that.
John Moloney was an Irish priest and author (1916-2014). I can’t find the lyrics anywhere on the internet so you’ll have to sing along from CWB II, unless you have the Irish version of Hymns Old and New.
I made up the chords for my backing and made it more Irish than French.