There's a lot of great scenes in The Fighter, but this is my favorite. Dicky, just released from prison, approaches his brother Micky's girlfriend Charlene, seeking permission to coach Micky again, a role he'd lost due to bad behavior (language is rough, BTW):
Dicky of course is a knucklehead and a crackhead. Having a conversation with Dicky means being treated to a steady stream of one-liners, stale jokes and out-and-out BS. Like the prophet Amos, Dicky lacks the proper history or credentials for telling the truth.
But tell the truth he does! And it's not a self-serving truth. A lot of people try to excuse their sins by appealing to the ubiquity of sin, but that's not what Dicky's up to when he reminds Charlene of her checkered past. Dicky realizes that Charlene's absolute moral superiority in this situation is getting in the way of Micky's success in the ring. It's Micky that Dicky cares about. If before he had wanted to be in Micky's corner to overshadow him, now he wants to be there to help Micky shine. But not by edging out Charlene.
And give credit to Charlene for accepting the truth. Because she really does enjoy an absolute moral superiority over Dicky. She's in Dicky's world, but no longer of his world. Her "balcony view" of Micky and Dicky's dysfunctional family has been invaluable to Micky in terms of his making the right decisions about his career. And yet she acknowledges that this crackhead is speaking the truth. She acknowledges that she can't give Micky everything he needs.
We know that Dicky is clean and sober because in the previous scene he'd given his birthday cake to his erstwhile supplier while declining his invitation to "go upstairs." Charlene doesn't know that. But she is able to recognize the truth when she hears it, and that leads her to trust Dicky.
Which is an extraordinary leap of faith. Addicts are notorious liars.
Legitimate truth-telling is always disinterested, and good listeners recognize and assent to the truth wherever they hear it. I think that this scene is a model for Christian conversation. Minus the F-bombs, of course.