"Onward, Christian Soldiers"

I usually don't write about the arrangements of hymn tunes, but a few months ago, I noticed something in the LSB arrangement of "St. Gertrude" (the tune for "Onward, Christian Soldiers") that I felt was worth commenting on.

Here's the melody and the bass part in the first line of the refrain:

In each of the first three measures here, the bass part alternates between two pitches.  Musically, this gives an impression of the "marching" that's in the text:  "Onward, Christian soldiers, / Marching as to war."

This feature is also present in the Lutheran Worship arrangement (#518), but it's not in The Lutheran Hymnal arrangement (#658).