Mark Wahlberg’s new movie “Father Stu” tells the true story of Stuart Long, an amateur boxer who becomes a Catholic priest while suffering from inclusion body myositis. The film is way more than just an acting gig for Wahlberg, who recently told Insider that he spent “millions and millions of dollars” of his own money to partially self-fund “Father Stu” when no other financial backer would take on the project. Wahlberg said he was partly inspired to do so by his co-star Mel Gibson, who spent around $30 million of his own money to help finance “The Passion of the Christ.”

“Well, I’m always willing to bet on myself,” Wahlberg said about partly self-funding “Father Stu.” “I slipped the script to a couple of people that I thought maybe would get it, and they didn’t. And obviously, it’s subjective. You have your own feeling of what the material is. Some people thought it was depressing because he’s sick at the end. They didn’t see the heart and the emotion and, ultimately, how inspiring it is.”

Wahlberg added, “I felt Mel had done it with ‘The Passion,’ so maybe I try it. And if I did find someone to finance, then that’s a whole other conversation because typically the person cutting the check also has notes and wants to be involved in the process. So I felt, you know what, I think it’s better if I just step up and have complete control.”

Asked how much of his own money he spent on the movie, Wahlberg responded, “Let’s just say I put millions and millions of dollars into the film — and then incurring other costs because we went over schedule in production, and there are clearances for the music.” Two of Wahlberg’s friends of also joined him in funding the project.

Variety film critic Owen Gleiberman called “Father Stu” an “awkward true story” in his review, adding, “It goes further into religious feeling than you expect, but you wish the drama were less sketchy… ‘Father Stu’ is not your everyday Hollywood religious odyssey — it’s closer to ‘Diary of a Country Cutup.’ It’s a surprisingly sincere movie about religious feeling, but it is also, too often, a dramatically undernourished one.”

“Father Stu” opens in theaters April 13 from Sony Pictures.