In "Savior of the Nations, Come," the first line of the fifth verse is "God the Father was His source," sung to this phrase (from the tune "Nun komm, der Heiden Heiland"):
"God" and "source" are both sung to a G notes, the tonic note of the tune (in G minor), so there's a mirroring between God as the "source" and the tonic note (the foundation) of the key.
The third line of the fifth verse is "Into hell His road went down," and - musically reflecting this going "down" - the melody (generally) descends:
The last line of the eighth verse (the last verse of the hymn) ends the doxology with "Now and through eternity," sung to this musical phrase (which is the same as the first phrase):
"Eternity" is sung with a melisma (Bb A G A G), and since the word is stretched out, there's something of a sense of that long period of time.
