Kidman said her 2001 divorce from her Scientologist husband of 10 years brought her closer to her father Anthony, a devout Catholic who is a biochemist and psychologist.
"When I was growing up, I was always much closer to my mother. Dad's a bit of a loner. He was always going off and reading books," Kidman told Britain's The Catholic Herald.
"But when I went through ... what I went through ... I found out who my father was.
"Because there comes a time when you're a daughter, that you suddenly need your father. And when you reach out for your father and he's there for you, well, that's a very special thing.
"My father really stood by me at a tough time. He was strong and dignified, and I'm very grateful that I do have a good father, because having him there with me at that time put me in good stead for carrying on with my life and learning to trust again."
Kidman married country singer Keith Urban in a Catholic ceremony in 2006.
"My father has a very strong Catholic faith, and I have never, ever heard him swear, which says something," Kidman said.
"He has a strong set of values, and he has passed his Catholicism on to my sister and me, but when he gives advice it's mostly based on being a good person, being tolerant, and doing unto others what you would wish them to do to you.
"So, yes, Catholicism is ingrained in me, but at the same time I pride myself on being open-hearted and open to exploring many other religions and ideas too."