Last month, I listened to a three-CD set of Les Paul (with Mary Ford, although she's not credited), and I realized that the lyrics in "Whither Thou Goest" come from the Bible, specifically Ruth 1:16. The first verse of the song is:
Whither thou goest, I will go
Wherever thou lodgest, I will lodge
Thy people shall be my people, my love
Whither thou goest, I will go
It's taken almost directly from the King James Version:
And Ruth said, "Intreat me not to leave thee, or to return from following after thee: for whither thou goest, I will go; and where thou lodgest, I will lodge: thy people shall be my people, and thy God my God."
For what it's worth, here's a video that walks through the original Hebrew of the second half of the verse: