Ian Buckwalter at NPR has reviewed Stone:

This is a film about people who are lost, and the filmmakers draw a direct line between their characters’ existential wanderings and the religious obsessions they find for themselves. For Jack, it’s the conservative Christian radio that soundtracks his commute to the prison; for his wife, Madylyn (Frances Conroy), it’s a deep involvement in their church.

I’m amazed at how many of these reviews have pointed to the “radio talk show” element in the film.