This is the 50th anniversary year of Hank Williams' death, but in 2011, Haggard co-wrote "The Sermon on the Mount" with the country archetype, arranging and adding music to a collection of Williams’ unpublished lyrics.
"I thought that was a great honor," Haggard said. "Bob Dylan was involved in that; Bob asked me to do that."
Yes, Bob Dylan, Haggard's old road mate.
"We toured a couple years together," he says, "all over the United States. Bob's quite a guy, he's hard to figure."
Haggard's been traversing the continent since 1965, when he first hit the road with his longtime band, The Strangers. The accolades are enormous: 38 No.1 country singles, thousands of recordings, hundreds of albums, several hall of fame inductions and universal respect among his peers.
Haggard sees no reason to quit now.
"We've played all over, and it's always different," he says. "Every time I make this cross-country trip, I think about retiring. I probably should've retired a long time ago, but I enjoy it. I don't know, it doesn't make a whole lot of sense (to retire) as long as I'm healthy. The attendance has been up the last few years.
"Haggard's written songs of a staggering variety — drunkard's laments, honky-tonk stompers, lovesick weepers, tender ballads, patriotic and protest anthems.
The urge to compose usually arrives in spurts.
"I'm an inspiration writer," he says. "I don't sit down and try to write. I write for the moment. It's been a dry spell, about eight or nine months since I've written anything. But I still try."
I fear I'm probing a sore spot, but I ask Haggard about his most famous song, "Okie from Muskogee." Released in 1969, "Okie from Muskogee's" lyrical content ("We don't smoke marijuana ... We don't make a party out of lovin' ") caused a cultural stir in Woodstock-era America.