Okay, all I know is the plot of the film, not who stars in it, but it’s a fairly recent film and I think that the main star was also a director/producer/writer (or some combination thereof) of the film.
In the film the father convinces his children that God has told him that certain people must die because they’re evil. There’s no evidence of this, but the kids help him whack the folks anyway. At the end of the film, you find out that dad might have been telling the truth and that the murdered folks weren’t as innocent as they first appeared. Any idea of what film I’m thinking of?