Let's look at the music

Here is the Old Hundredth the way it is usually written.

Click on the image to see it larger.

Now one thing is obvious and that is that I will want to transpose this so I'm not singing in the sub-basement to hit the lowest notes. But that is the easy part. I think I'll kick it up to the key of D.

The more difficult thing is all those %$#&ing chords. Why does such a  simple melody need such a lot of chord changes?

The mystery deepens when you consider that all of the chords used are diatonic chords for the key of G. That is to say, they are all the most obvious, basic chord choices possible. If they were adding colour and interest it would be easy to accept all the changes but they aren't. They are, in fact, making the melody drab and boring. So why are there?

The answer is that they are there as a crutch for the congregation. If you check—and I have—you'll notice that every single melody note is somewhere in the accompanying chord. This makes it very easy for a group of amateur singers to sing along and all stay on the melody. The church organist, meanwhile, was paid enough that he or she could be expected to make all the changes without any trouble.

But for our purposes, the hymn will be more challenging and interesting and beautiful if we can dump some of these chords. But which ones? There I am a bit challenged. I know it can be done and I've seen others do it but I don't really know how to do it myself. So I'll have to see if I can figure it out.