11/08/2013 09:42 am ET

Mark Nepo On The Devastating Diagnosis That Began His Spiritual Journey (VIDEO)

Nearly 26 years ago, poet Mark Nepo discovered a lump on the back of his head, which would later be diagnosed as cancer. In the above clip from an upcoming episode of "Super Soul Sunday," Oprah asks the bestselling author to go back to the life-changing moment that ultimately led to a profound spiritual awakening.

Nepo says it "seems like yesterday and a lifetime ago" that his cancer journey began. "Back 26 years ago I was in a former life and a former marriage and I had this lump start to grow, and it was huge. I had never been ill, I had a lot going on -- I didn't really pay much attention until an old friend said, 'I think you're growing a second head. You better look at that.'"

Nepo agreed to go, but saw a sports medicine doctor. "Because I didn't think anything was wrong with me," Nepo says. "And he said, 'I think there's somebody else you should see.'"

The moment he learned he had cancer was a dividing line in his life, Nepo says.

"And all of a sudden, as I think most people experience, I went through a door," he says. "And when I went to go back out that door, it was gone. There was no way to get back to the life I had lived. Everything had changed."

"Super Soul Sunday" airs Sundays at 11 a.m. ET on OWN.



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