Dr. Brian Weiss On The Patient Who Convinced Him There Is An Afterlife (VIDEO)

Past lives, the afterlife, channeling messages from beyond the grave -- some people call it fascinating, others call it frightening. And then there are the many skeptics who call it pure fiction. Dr. Brian Weiss, an Ivy League-educated psychiatrist, used to describe himself as one of those skeptics. But Weiss' views completely changed in 1980 when he met a patient he calls Catherine.

While undergoing hypnosis for anxiety and depression, Catherine began recalling inexplicable memories from another time and place, and also revealed startling personal details about Weiss that he says she had no way of knowing. In this clip from Weiss' upcoming appearance on "Super Soul Sunday," he recalls several moments from Catherine's life-changing hypnotherapy session.

While Catherine was under hypnosis in 1980, Weiss says his office suddenly became icy cold. The patient began to speak.

"She said, 'There are two people here to see you: your father and your son,'" Weiss remembers Catherine telling him. "She didn't know anything about me. I don't even have diplomas hanging in my office... It was before the Internet, before you could Google your doctor."

Catherine then told Weiss facts she couldn't have known. "She tells me my daughter is named after [my father]… She said, 'Your father is here; he died from his heart'... And she went into other medical details."

Weiss was shocked. "I'm thinking, 'What is this? How does she know this?'" he recalls. "[My father] never had an obituary… Our best friends didn't know the details."

But Catherine wasn't finished. "She said, 'Your son is with him; he's here too. He's very tiny… And his heart is important also because it's turned around backwards.' And she went into why he died -- medical details," Weiss says, referring to the 23-day-old newborn child he lost to a rare congenital heart deformity in 1971. "That was the epiphany for me. That was the moment I knew."

Watch Dr. Weiss discuss more about his research into the afterlife and past lives on this week's "Super Soul Sunday," airing June 2 at 11 a.m. ET on OWN.

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