Vera Farmiga knows she has a hard sell with “Higher Ground.”

The deeply affecting film, adapted from Carolyn Briggs’ 2002 memoir “This Dark World: A Story of Faith Found and Lost,” isn’t merely about faith. It’s about questioning spirituality, wondering if and when it’s enough, and the realities of living an evangelical life.

“I will never have more challenging discussions than I do with this film. I miss the days of being asked what it’s like to kiss George Clooney,” she says, unleashing an infectious laugh.

In town recently to discuss “Higher Ground,” Farmiga, most known for her Oscar-nominated turn in Clooney’s “Up in the Air,” is tucked into a chair in a stately library room in a residence at the Four Seasons in Midtown. She is unconventionally lovely, casually clad in jeans and a loose T-shirt, her searing blue eyes a contradiction to her gentle demeanor.

She chooses her words thoughtfully when responding, often pausing for several seconds when explaining the complicated journey of Corinne, the character she portrays, whom we follow from a repressed childhood to an inquisitive adulthood.

“The point of the film is not to persuade or convert or to turn people away [from religion]. It’s basically saying it takes great striving and [we should] appreciate this woman’s journey. Have compassion. In many ways, it would be easy to switch to either direction, but that wasn’t the story. The story is that there are ebbs and flows, ups and downs, there are hiccups. It’s not just about your relation to whatever conceptualization you have to whatever deity,” Farmiga says, then pauses. “It’s just to come from an authentic place.”

In addition to being “Higher Ground’s” commanding presence, Farmiga, 38, also makes her directorial debut with the film, a task she undertook while pregnant with her second child, daughter Gytta.

Initially, the directorial duties belonged to Tim Metcalfe, who co-wrote the screenplay with Briggs. But when Metcalfe sent Farmiga the script and suggested she direct it, the actress was immediately intrigued by Briggs’ “very specific voice.”

Then obstacles popped up, such as Farmiga’s pregnancy and troubles with financing the film.

She thought about bailing on the project, but by then, “I had Carolyn’s confidence. If I didn’t have her enthusiasm for the idea and then, miraculously, financing came in to shoot the movies six miles from where I live in upstate New York — I kept trying to say no and every time I tried, something else prevented me from doing it,” Farmiga says with a laugh.

Though she says she had no expectations as a director, Farmiga did have specific ideas for the film, such as making music an integral part of Corinne’s story.

She also turned “Higher Ground” — named after the hymn — into a small family affair, with several generations making appearances.

Her sister Taissa, 21 years her junior, plays a compelling younger version of Corinne with an effortless grace that belies her inexperience as an actress (her only previous acting came in a second-grade play).

But the youngest of the seven Farmiga children wasn’t exactly looking for favors via nepotism.

“I put a gun to her head. She had no choice in the matter,” Farmiga says with smile. “I told her, if you want my red carpet hand-me-downs, then you are doing this. I also persuaded her with a 2004 Toyota Tacoma when she turns 18. But now that she’s shooting her own TV series in L.A. [“American Horror Story”], we probably have to renegotiate.”

Farmiga said the experience drew the already-close sisters even tighter, as they together delved into Corinne’s psyche.

Farmiga’s toddler son, Fynn, is also in the film as the younger Corinne’s son; her sister Molly plays banjo in a church scene; her mother does some background work; and her cousin is responsible for the creative sculptures and drawings in the film.

But for Farmiga, the most important family connection was sharing a scene in a home for the elderly with her grandmother, who has advanced Alzheimer’s.

“I wanted,” she says, “to commit her to film with a smile on her face.”