Sometimes you find comfort in unusual places. It was 1997 and I was living in Japan, teaching English to middle school kids. I lived in a tiny village, and in those early days especially, I was pretty lonely. Except for my good friends Jean Luc and Data.

The teacher who had lived in my apartment before had left a huge box of VHS tapes – there were enough episodes of Star Trek: The Next Generation to keep me company for the duration of my time there. Don't worry, I made real life friends in Japan, but that show – those characters navigating the galaxy – were an important touchstone as I explored my own new world.

For the most devoted of fans, Star Trek: The Next Generation represents much more than just a TV show. And this is not lost on Sir Patrick Stewart, who played the captain of the Starship Enterprise on The Next Generation for seven seasons and four feature films, and stars in the latest TV iteration of the franchise, Picard.

"The Next Generation's impact on so many people has been extraordinary," Stewart told me. "Ranging from people saying that it became their English language education to someone who said, 'I was going to end my life, but I couldn't because I wouldn't be able to see Star Trek anymore.'"

Stewart has just released a memoir, Making It So, taking its title from a Picard catchphrase. We talked about his life on screen and stage, and why he considers those years on Star Trek as a kind of spiritual calling.

This interview has been edited for length and clarity.

Rachel Martin: There is a bit in the book, early in your career, I think it was your first job, but you were an assistant stage manager. It's your first job in the industry and you write this beautiful description of what it felt like to be on the stage, and I wondered if you would read that for me.

Patrick Stewart: Yes, I can:

At the end of each performance, I waited for the last actor and the staff to leave the theater before switching off the lights and locking up for the night. Actually, I left on one light in accordance with an old theater tradition, whereby a single bare bulb is left on, hanging over the center of the stage.

With the theater otherwise deserted, I stood beneath this light every night, taking a moment to breathe in the auditorium and the vibrations of the audience that had just left it. I looked at the set, only recently populated by our company of actors. I was part of all this now. Indeed, I had responsibilities to fulfill, even if they were as a lowly assistant stage manager. This, I thought, is now my home.

Martin: Maybe I am projecting, but there is, I think, a sacred quality to how you describe that space. Is that accurate? Did you sense that kind of reverence or sacredness about the theater?

Stewart: Oh yes. To stand in the middle of an empty stage in an empty theater and feel that I was at home was everything. But it took a while for me to get there.

Martin: Did you feel that on a television set?

Stewart: No. I didn't. Cameras made me nervous.

Martin: You were not Gene Roddenberry's first pick to play Jean Luc Picard. Taking this role was also going to take you really far from your wife and kids who lived back in England. Why did you take it?

Stewart: I wasn't going to take it. Indeed, a dear friend of mine and a very important English actor had said to me, "Don't do this, Patrick. It's not what you need to do. You're a very good stage actor. That's where you ought to be. Don't do it."

I had learned that the contract that I was being offered was for six years, but I was told we would be lucky to make it through the first season. I remember one actor saying to me, "Sign up for this. Do six months of work. Make some money for the first time in your life. Get well known, get a suntan and go home."

And I thought, "Yeah. That doesn't sound too bad. I could live with that." And, of course, our first series lasted seven seasons. And then we made four feature films.

Martin: I talk to a lot of people about spirituality and about the value of spiritual communities, which I think are when people who have similar values gather together and have or seek transcendent experiences. And I think Star Trek, in all of its incarnations, represents that to a lot of fans. It is a spiritual world. They treat it with religious reverence. Have you encountered that? Do you get it?

Stewart: Yes. I see it very, very clearly and very strongly. It was about truth and fairness and honesty and respect for others, no matter who they were or what strange alien creature they looked like. That was immaterial. They were alive. And if they needed help, Jean Luc Picard and his crew, his team, were there to give it.

In a sense, we were ministers. And I have heard now so many times from individuals who have been honest enough and brave enough to tell me aspects of their life, of their health, of their mental health. And how it was all saved and improved by watching every week.

Martin: How did that sit with you? That's an awful lot of responsibility to be that. I mean, you're an actor in a show and people ascribe to you this wisdom, you're a moral compass for them.

Stewart: I was proud of it and what we did. And I talked to Brent Spiner and Jonathan Frakes and Marina Sirtis and Gates McFadden and Michael Dorn, LeVar Burton. We talked about this kind of thing often. And it's a glorious feeling because we were just having a good time. We loved our jobs.

Martin: Didn't that feel incongruous that you're acting and you're having fun but it had this profound impact?

Stewart: No. It didn't feel at all incongruous. Particularly given the role I was playing. This was a man of such profound understanding and empathy. And to feel like that as a person was such a reward for what we were doing because we were enjoying our work but at the same time we were changing people's lives.

Martin: Did playing Jean Luc Picard Make you a better person?

Stewart: It gave me an idea of how I might become a better person, yes. I was able to absorb that and make those feelings a strong and firm part of my life.