Transcript for Ex-Scientologist Says He Was Asked Profane Questions as Minor in Training: Part 4
I want them to know that I'm here. I want them to know that I know. Reporter: Serge Gil is not a celebrity. Not a battle-hardened, book-publishing, semi-professional scientology critic. He is someone who spent his entire childhood in the church, and tonight, he's talking about it for the first time. This is why it's so important that I come forward, because I feel like, you know, we lived it. We lived the hell. Reporter: Serge was born into a large scientology family. His parents were devout parishioners who, serge says, he didn't see so much, because they were so busy doing the work of the church. My first memories of my childhood were already inside this organization. Reporter: At age 10, serge says his parents enrolled him in a course which involved an introduction to auditing techniques. Auditing is one of the central practices of the church. It's a kind of therapy using a device, invented by L. Ron Hubbard, called an e-meter, which is supposed to help liberate you from negative feelings and the trauma of past experiences. This is just a flow of energy that's coming from the meter through you, back to the meter. But once a thought comes in, that thought, that picture that you have, that is registering on the meter. Reporter: Leah remini gave me a small taste of what she says an auditing session is like. You'd be asking me questions? I would ask you questions. And based on what's happening here, would I let you get away with it or not? You see what I'm saying? Reporter: Serge says as part of his auditing training, he had to talk adults through traumatic experiences in their lives, including a fatal car crash and a sexual assault. Why would they want children doing this? Because L. Ron Hubbard doesn't consider that children are children. You are an ageless spirit. So, your body is catching up to your spiritual age. Reporter: Do you think that kind of material is age appropriate? Well, I don't think that that kind of material is necessarily age appropriate, but I also don't think that that necessarily happened. I can't say that it's never the case, but the church has very, very strict protocols in place, as to how children are raised in scientology. So, it would not fit within those standards for that kind of a thing to happen. Reporter: Serge says that was not his experience. He says by age 12, as he continued his scientology indoctrination, he was put through a training routine known as bull baiting. Where I'm sitting in front of someone in the same setting we are right now, but I'm 12 years old. And your job is to find what kind of thing could make me react. Reporter: Leah says she also remembers bull baiting vividly from her childhood. You have to sit here like this. And you cannot move. So, I say, okay, start. So Dan, you think you're Smart and bright? Do you know that -- whatever. I'd get some On you and say it and hope that you didn't react. And if you reacted, they'd go, "Flunk. Start." They'd do it again. They'd keep doing it, until you were no longer -- had a reaction to that. Reporter: Leah says bull baiting could sometimes include sexual language, something serge says he experienced as a minor. You know, do you -- just profane. Reporter: We've spoken to a number of former scientologists who say, in the process of participating in bull baiting, they encountered provocative sexual language from adults. What's the church's reaction to that? I can't say that never happens or that it has never happened. But if it were brought to the attention of the church, it would be dealt with very strictly and very firmly. And the church does not put children in the situation where those kinds of things could happen because they normally would be in training classes whatever with people of the same age group. Reporter: Monique Yingling says that bull baiting has an important purpose, to prepare a scientologist for the intensity of auditing. And, in fact, serge says that when he began auditing, it did indeed get intense. They ask you questions, Dan, where, if you don't have a sexual past, "Have you ever raped someone," if it read on the machine, I would be told to look into a past life. So, I have to fan that size about raping somebody, in order to answer the therapy question. Reporter: Did you ever raise your hand and say, this is really making me uncomfortable, I'm too young for this? The problem with this, Dan, is that the adults are praising every single one of your moves. They considered me a superstar. Reporter: Serge claims he was asked that question about rape when he was 14, and being administered something called the johannesburg confessional. Some of the questions on there include, "Have you ever raped anyone? Have you ever had intercourse with a member of your family? And have you ever practiced sodomy?" And there are many more. Do you think this is age appropriate? So, those questions might be appropriate to a 14-year-old like Sergio Gil. I don't know. I do happen to know, because I've been told, that he was not asked those questions. And that was because whoever was administering the confessional had decided that those questions should not be asked. Reporter: But you conceive of occasions where it would be appropriate to ask a 14-year-old questions like that? It depends on the 14-year-old. What I can tell you is that it would never be used in an inappropriate manner by the church. That normally, it would not be asked of a 14-year-old, and if it were, it was because, under the church's very strict protocols, it was decided that it was an appropriate question. Reporter: While the church insists the johannesburg confessional is rarely used on any parishioner, including adults, they did provide us with this confessional, written by L. Ron Hubbard, specifically for children as young as 6. The first question is, "What has somebody told you not to tell?" Another question is, "Have you ever done something to your body you shouldn't have?" And another question after that is, "Have you ever done something to somebody else's body that you shouldn't have?" You can do lots of things to your body. You know, you can cut your body, you can hit your body, you can, you know, cut your hair, you can do whatever. Reporter: Yeah, but this is a question for somebody as young as 6 years old. Don't you see how that could pretty easily lead to something sexual? It possibly could, but that doesn't mean that whoever is ministering the confessional would take it down a sexual route. Reporter: But you're a parent and a grandparent. Do you think there are any circumstances under which it would be appropriate for somebody who is 6, 7 years old, to be alone with a grownup, asking a question where there are some odds that it could turn into a discussion of sexual content? I happen to raise my children catholic, and they went to Sunday school and they were alone with priests. And certainly something sexual could have come up. Reporter: There's no form like this where there are questions that, I think we can all agree, might lead to sexual content, in the catholic church that I'm aware of. If I put my child in the in the care of my church or my minister, I have faith that that's going to be handled properly. And I think that's the same thing that scientology parents do with their children. Reporter: The church says that, as with other religions, its indoctrination of children is constitutionally protected, when done with parental consent. And they sent us these video testimonies of parishioners who were raised in the church. I'm very grateful to have been raised a scientologist. I took my own first steps in scientology when I was about 9. I realized that when I was going scientology, I was doing better in life. Reporter: However, "20/20" spoke to a number of former scientologists who, like serge Gil, say that sexually explicit subjects were a part of their scientology indoctrination as children. I really question the credibility of those individuals, and I think you should, too. Reporter: Are you saying all these people are making this up? It's not to say that one person might not have had one incident, but the stories that you're being told are either false, completely exaggerated, or made up. Yes. Reporter: But serge says his story and his trauma are real. Coming up, how serge left the church, and why he turned for help to the very people scientology deems most dangerous. Finally, I had someone -- who had a clinical understanding of what was done to me.
This transcript has been automatically generated and may not be 100% accurate.