The 43-year-old actress stunned on the red carpet, wearing a sleeveless, little black dress to premiere in Dallas, Texas Sunday night. After the screening, she joined the film's producers DeVon Franklin and Bishop T.D Jakes for an audience Q&A.
In the upcoming drama, Garner plays a mother whose faith is restored when her daughter is cured from a severe digestive disorder after falling 30 feet inside a hollow tree. The movie is based on the real-life saga of Texas mom Christy Beam, who joined Garner on Monday for a Good Morning Texas appearance in Dallas.
Garner, who was born in Texas, was asked by host Jane McGarry why she wanted to do this particular movie: "Did you want to talk about faith and God?"
"I love the message in the film, and I love the message of hope," she says. "I love how inspiring the film is. But I also really connected with Christy just from reading the book and from reading the script, and I wanted to honor what she and Annabel and the whole family went through."
Asked if she and her children go to church, Garner said they do.
"Is that weird in Hollywood?" McGarry asked.
"You know, it did seem strange," she replied. "I grew up going to church every Sunday of my life, and when I did move to L.A., it wasn't something that was just part of the culture in the same way, at least in my life. But it didn't mean that I lost who I was. But there was something about doing this film and talking to my kids about it and realizing that they were looking for the structure of church every Sunday. So it was a great gift of this film that it took us back to finding our local Methodist church and going every Sunday. It's really sweet."
Annabel Beam, the little girl at the heart of the movie and the book by the same name, had suffered from pseudo-obstruction motility disorder for years. The disease often required tube-feeding and hospital stays. But after falling 30 feet into a hollow tree – and visiting Heaven, she says – Annabel became asymptomatic.
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In a scene from the movie, Garner asks the doctor, "You're telling me that when this baby girl fell 30 feet, she hit her head just right and it didn't kill her and it didn't paralyze her and it healed her?
"Yes," the doctor says.
"That's impossible," she replies.
On Good Morning Texas, Garner was asked if she believes Annabel's account that she went to Heaven.
"Nobody who meets this child, with her sincerity and her frank honesty and faith, would ever think for a second that this child is making anything up or is being sensational," she says. "She is just true to the bone. That's just who she is.
"She is an old soul," Garner adds. "There's something very special about her. She can be very internal and quiet, but in the next second she's just a little girl running around and eating fettuccine Alfredo. I learned so much about this disease that when I sat down with her and she had a plate of pasta in front of her, there was a part of me that felt like, 'You can't eat that!' But she's okay; she really is. It's a miracle."
Although she says she doesn't ever "put my children in peril in my mind" while acting, Garner does think that being a parent herself helps her immerse in these types of roles.
"I do think that being a mother of three has opened my heart in a way, and that helps me access that ferocity that all mothers feel for their children," she says. "It's not unique to me."
Asked if she uses her faith to overcome personal challenges, Garner says, "Of course. I think that's what it's all about. But there's a beautiful line in the movie that really resonates with me; Christy is having a conversation with her pastor and she says, 'I just don't understand. I don't know where my faith is right now.' She's in the crisis of faith. And he says to her, 'You know, everyone is going to struggle and I look at it this way: I've struggled with faith and I've struggled without it. And I'll tell you, it's a whole lot easier with.'"
Over the weekend, Garner and Beam attended a service at The Potter's House Church, led by Bishop T.D. Jakes, a producer on the movie.
"I loved it," Garner said of the experience. "I'm so jealous of the people of Dallas that they can draw from T.D. Jakes and can go every week to hear him preach."
One message of the movie is that everything – even the little things in life – are miracles. Garner says she can relate.
"It's also what my mother has instilled in my sisters and me so much, that joy comes from the smallest things," she says. "And if you don't see joy in a perfect avocado or in a great conversation or in running into a friend or getting a job – if you don't see joy in a perfectly beautiful tree in autumn – then you are missing your chance at happiness. Because if you don't find it in the small things and you only wait for big moments, then you'll just not be a happy person."