In the film Reverend Carter declares, "My daddy used to say..." In real life, the father of the actor delivering that line is Morgan Freeman.
The scene in the hallway between Odell and The Reverend was actually filmed after dark. The DP and Gaffer lit the outside windows to make it appear like sunlight was streaming in.
The film is based on a true story chronicled in Bishop William Willimon's book, Accidental Preacher: A Memoir. The future Bishop of the United Methodist Church walked out of his church as a humiliated confirmand, when his minister stopped him and learned the full story.