What's going on here?

Here is another of what I will call an "unconventional hymn" from The Mennonite Hymnal. Click to enlarge.

With original German words by Martin Luther and later translated to this English version, with a melody that is also from the early 16th century but harmonized some 200 years later by that master of the baroque, J.S. Bach.

At first glance I thought, hey, I've found a hymn in Dorian mode! But on looking through it more carefully, I don't think it really fits into Dorian. Of course, I was never really trained in composition for all the various modes so I could still be wrong.

All those accidentals, and especially the flatted Tis are what have cast me into doubt. It does look like the sharped Do and the use of a G in the tenor creates a dominant seventh chord in the last measure that throws it firmly into the key of D for the last note. It does have a sharped Fa that makes it a D major chord, but we can just call that a Picardy third.

In any case, I think I will have to transcribe this song into Melody Assistant so I can play it and see how it all sounds.

Check the link for the Dorian mode above for a short list of pop songs in Dorian mode. I'm sure everyone is familiar with at least two or three of them.

Oh yeah, and check out those low notes in the bass part. Not many amateur singers could pull that off, I'd guess.