I kept talking to my producers at Columbia about recording one of those [prison] shows. So we went into Folsom on February 11, 1968, and recorded a show live.

I started to write the song. And I was in Gladewater, Texas, one night with Carl Perkins and I said, I've got a good idea for a song. And I sang him the first verse that I had written, and I said it's called "Because You're Mine." And he said, "I Walk The Line" is a better title, so I changed it to "I Walk The Line."

Sam Phillips asked me to go write a love song, or maybe a bitter weeper. So I wrote a song called, "Cry Cry Cry," went back in and recorded that for the other side of the record.

It was kind of a prodding myself to play I Walk The Line straight.

I keep a close watch on this heart of mine I keep my eyes wide open all the time I keep the ends out for the tie that binds Because you're mine, I walk the line.

Gospel music was the thing that inspired me as a child growing up on a cotton farm, where work was drudgery and it was so hard that when I was in the field I sang all the time. Usually gospel songs because they lifted me up above that black dirt.