I found the lyrics!

Found a lovely recording yesterday called "Gentle Words: Shaker Songs arranged by Kevin Siegfried," performed by the Tudor Choir. It includes "Hunger and Thirst" (not, as I'd written, "I Hunger and Thirst.") These are the lyrics:

I hunger and thirst after true righteousness.
In what I've obtained, my soul cannot rest.

An ocean I see, without bottom or shore.
O feed me I'm hungry, enrich me I'm poor.

I will cry unto God, I never will cease,
'Til my soul's filled with love, perfect love and sweet peace.

It was written in Alfred, Maine in 1837.

Many thanks for all your help and suggestions.

Cheers,
Muggletonian