G'day Neil,There seems to be a pretty close correlation with the words you quoted. Either it is the same song ... or Sydney Carter was paraphrasing some other text which has inspired another writer as well.
The date seems to confirm this one: I heard Sydney Carter sing it in Canberra 27½ years ago and he published it some 31 years ago. 25 years is long enough for the mind to have shuffled a few lines around and reshaped it to your own ideas.
The tune can be pretty flexible in Sydney Carter's work. I think I may have heard this done by him as a recitation as well ... and he did write a poem/song saying that words and music are not wed ... they are just good friends!
Regards,
Bob Bolton