Oprah sees Dr. Maya Angelou as a mother, a sister and a friend. It's a relationship that began nearly 40 years ago when Oprah, then a young reporter, asked the literary icon for an interview, promising to take no more than 5 minutes.

Dr. Angelou agreed to the interview only because of Oprah's persistence and was impressed by her questions and interviewing style. But the poet became particularly intrigued by the curious young woman in front of her when she realized that Oprah had kept the interview to five minutes on the dot.

"In my memory, you said, 'Who are you, girl?" Oprah says as the two recall the fateful meeting during a 2013 episode of "Super Soul Sunday."

Despite their long friendship, Oprah still discovers things that surprise her about Dr. Angelou. As an example, she shows a clip from the 1957 film "Calypso Heat Wave," in which Dr. Angelou starred as Miss Calypso.

Dr. Angelou still remembers the words. "It's amazing, I'm grateful that I had a chance to do that," she says, smiling.

Oprah asks Dr. Angelou what advice she'd give her younger self.

"I would encourage her to forgive," Dr. Angelou says. "It's one of the greatest gifts you can give to yourself, is forgive. Forgive everybody. Just forgive it."

"You are relived of carrying that burden of resentment," she continues. "You really are lighter. You feel lighter. You just drop that."

She goes on by opening up about one of her most difficult trials in forgiveness. "I had to get to a place where I could forgive the man who had raped me when I was 7 years old," Dr. Angelou says. "I had to get there. And that was a matter of incredible mental gymnastics. And then I had to think of what I had done to other people and see how I'd been forgiven. Whatever I've done, I've been forgiven, and I have to get, at least, to a place where I can forgive."

"I don't forget, and I will not put myself in a situation where that can be done to me again, but I understand," she says.

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

