John Travolta appeared on “Good Morning America” to promote his upcoming movie, “The Forger” but he also answered a couple of questions about Scientology. 

The 61-year-old actor has been a Scientologist for more than 40 years. A recent documentary on HBO called “Going Clear” has placed a harsh spotlight on the Church of Scientology and discusses Travolta extensively. Travolta did not appear in the film and decline to comment for it. 

“People really need to take time and read a book,” he said on Good Morning America. “You know, that’s my advice. You could read 'A New Slant on Life,' you could read 'Dianetics.' And I think if you really read it, you’ll understand it, but unless you do, you’ll speculate. And I think that’s a mistake to do that.”

He further added that Scientology has helped “save lives” including his own and that it’s become a target because it “really works well.”

"Sometimes when something really works well, it becomes a target," he said. "Forty years for me, I've been a part, and I've loved every minute of it. My family has done so well with it. It's been a beautiful thing for me. I've saved lives with it and saved my own life several times. Through my loss of my son, it helped me every step of the way for two years solid, and here I am."

Travolta and wife Kelly Preston’s eldest son, Jett, died suddenly at the age of 16 in 2009 from a seizure. Jett had a history of seizures and was autistic.