This is a good song. I have it in the book "Johnny Cash: The Songs",
(a lyric book of just songs and poems that he wrote)
I first heard it when I watched the 1969 film Johnny Cash: The Man,
His World, His Music. (I remember that the second verse wasn't played in the movie, though).

When he sings "But I know a way for a man to go free", I'm reminded of
the line "I first set my sights on Sweet Molly Malone", from
Cockles and Mussels. (But just in the melody of that particular
phrase).