Cronenberg is said to describe himself as "not just an atheist, but a total nonbeliever."
From an interview in Film Threat, February 1997, p. 11:
Q: Most of your films deal with various characters' personal spirituality, yet you have never dealt directly with religion.
A: The reason why is that I'm not interested. You're absolutely right. For me, it's not even worth discussion. It doesn't interest me. It interests me only to be discarded. If I start there, I'm mired in a discussion that is very unfruitful to me. I'm simply a non-believer and have been forever. To discuss religion is to put me in a debate with myself. I'm interested in saying, "Let us discuss the existential question. We are all going to die, that is the end of all consciousness. There is no afterlife. There is no God. Now what do we do." That's the point where it starts getting interesting to me. If I have to go back and say, "What if there is a God?" then I'm doing a debate that is not very interesting. You have to create one character who believes and another that doesn't. It's not an issue.
and on pp. 11-12:
Q. How were you raised?
A. I'm an atheist and my parents were both atheists so it was never a big issue, and if I wanted to become an Orthodox Jew, it was never, "You must not do that." And I certainly went through all those things as a kid wondering about the existence of God or not, but at a very early age, I decided we made it up because we were afraid and it was one way to make things palatable.
"I'm an atheist," Cronenberg said. "To me an act of murder is the act of total destruction, it's absolute. There's no comeback, there's no going to heaven, that's it. And it is very easy for that to be veiled or covered up, in a movie especially.