I learned and sang Nun danket alle Gott
as a bass singer when I was a member of Die Zeitlupe
some time in 2006.
The original melody was by Johann Crüger
and the words by Martin Rinckart (1618). It was then arranged by Johann Sebastian Bach
as a "Trauungschoral" used at weddings and state occasions.
The version we sang is given in Bach Choral Gesänge
on page 176.