Sony Pictures Entertainment

It shouldn't come as a surprise that Mark Wahlberg is friendly with Tom Brady. Besides hailing from Boston, where Brady and the Patriots owned the NFL for the better part of two decades, the Academy Award-nominated actor is arguably just as famous for his diet and fitness regimen. But Wahlberg's latest role, for Sony Pictures' upcoming Easter Week drama Father Stu, required preparation that even Brady might've balked at.

A true story based on the life of Stuart Long, a boxer-turned-priest who later battled a muscular disease, Father Stu is something of a passion project for Wahlberg, a devout Catholic. (He's been aiming to bring it to the big screen since local priests told him Stuart's story over dinner more than five years ago.) That passion helped him put on 30 pounds to accurately portray Stu, all in a matter of weeks. First it took 7,000 calories a day. Then 11,000 daily for the four-week home stretch of filming.

"I would love to sit here and say -- you know, chocolate chip cookies are my favorite -- so I'd love to say that I had some chocolate chip cookies and wine at the end of the day," Wahlberg said in an exclusive interview this week, "but I had to eat and consume so many calories, and tried to do it in a healthy way, that by the time it came to having a little cheat meal, you didn't wanna do anything other than just lay down. I mean, it felt so bad. But the journey -- the spiritual journey, the physical journey -- were such critical parts to the story."

Catch Cody Benjamin's full interview with Mark Wahlberg right here:

Ballooning his weight wasn't the only goal. Getting fit was also key for Wahlberg's scenes as a boxer. Fortunately, he has experience playing an athlete, starring as bartender-turned-Eagles player Vince Papale in Invincible (2006) and former pro boxer "Irish" Micky Ward in the Oscar-winning The Fighter (2010).

"I still approach every movie that I do as an athlete," Wahlberg said. "I always look for something that I have to do physically to prepare, as well as learning my lines and becoming the character. I always approach it like I gotta be ready before I get there, so when it's game day, all the preparation has prepared me, I can throw all that out the window and just react to whatever's going on at the time. But yeah, certainly the six years of training and boxing to play Micky Ward, and kind of getting back in that same routine with the same group of people (was helpful)."

Not only that, but Wahlberg revealed Father Stu just might be the catalyst for another return to the ring.

"Actually, now, we've started having the first conversations about doing The Fighter 2," he revealed, "which I know I'm on the cusp of being too old, but it'd be much more about flashing back to the Micky Ward-Arturo Gotti trilogy, but really kinda focusing on the relationship and the bond that was formed through the battles and how they became brothers."

Truth be told, Wahlberg gravitated toward Father Stu, which co-stars Mel Gibson and releases exclusively in theaters April 13, because of the spiritual dynamics. He credits God and his wife, Rhea Durham, for his own turnaround from teenage convict to movie star and family man. And he saw instant parallels between his journey and that of Stuart Long.

"I think the project kinda chose me," he said. "I think this is certainly the most important role I've played to date ... I've spent the last 30 some-odd years -- 40 years -- preparing to play this role, personally and professionally."

And Father Stu is not, he assures, a stereotypical "Christian movie." Wahlberg is clear that he wants devotion to God to be celebrated here, especially during a time when "people are kinda shying away from faith." But he's committed to telling Stuart's story as it was -- raw and rough and not always family-friendly.

"Aside from the priests who brought (the story) to me and a couple that knew me and knew what I was really trying to do," Wahlberg said, "we got a lot of push-back initially from people of the cloth, just because of the language and they didn't understand why we had to push the envelope and make it more real and more gritty -- you know, it being an R rating -- but it's truthful. It's far more relatable to people, and we want everybody to see this movie."

That includes Tom Brady. And who knows? Maybe someday Wahlberg will repay him by bringing the QB to the big screen next.

"There is no Patriots movie on the radar," he confessed, "but I'm obviously friendly with Tom, and they always say, 'Would you play Tom Brady?' I don't think -- I'd be a much better Bill Belichick than I would a Tom Brady. But that would be fantastic."