The film, based on the 2008 memorial written by King's fiancée Dana Canedy, follows the true story of a King who is deployed to Iraq in 2006 while Canedy is pregnant. While serving, he pens an advice journal for his soon-to-be-born son Jordan.
During the promotion of the film, Jordan told Fox News that putting on the military uniform carried extra responsibility.
"To put on the first drill sergeant uniform [with the] patches and the dress blues, [there's] a certain confidence and respect that comes with it," he described.
The "Creed" star added, "So [the uniform] definitely made me stand a bit taller, talk a little bit stronger, louder… It just definitely added to the performance I tried to give."
The movie is directed by Oscar-winner Denzel Washington who said he's stolen bits of wisdom from every person he's worked with during his career and applied the accumulated knowledge to his own sets.
"I've learned from different filmmakers that I've worked with, different actors I've worked with," he told Fox. "I've had the opportunity to work with some great filmmakers. So you just, you know, take a little bit, you mature, you learn what to get rid of. You simplify."
His technique is much appreciated by his cast. Chanté Adams, who played Dana in the drama told Fox about a very emotional scene she was nervous about shooting.
"Denzel was like standing at the door and I was going into my trailer," she recalled. "He just walks to me. He puts his hand on my shoulder, and then he prayed over me. And that was just a really powerful moment because he knew that I was feeling a lot of pressure about doing that scene."
Meanwhile, Canedy told Fox the scene King would have loved the most was when he met his son for the first time. She felt relief at how collaborative the creative process was with Washington at the helm.
"We were all on the same page. We worked together because we knew we were about to put something very special into the world," she said of her and King's love story.
"Journal for Jordan" is currently in theaters.
FOX's Ashley Dvorkin contributed to this report.