When writing Christian fiction, remember the most important rule – the story comes first! No matter how worthy the message, if the story doesn’t captivate and interest the reader, they’ll never complete the story and will therefore never receive the message.
Also, make the story realistic. Not everyone gets saved. Bad things happen to good people. Simple characters, like those who are all good or all bad, are uninteresting. If your protagonist is perfect and never changes, never struggles, no one will relate and no one will care about your story.
Again, the story comes first! No one wants to read a sketch written around a sermon and the sermon changes everything. There’s no struggle, there’s no conflict, there’s no drama. A discussion can occur with a point or two, but there better be a huge build up to make the person receptive to hearing the point(s), and it should be directly related to the story. It would be much, much better that the lesson is taught through action, not someone just talking. Most Christian movies have a sermon as the major turning point. The audience, all Christians, walk out thinking it was a wonderful example and never again think about, let alone rent or purchase, the movie.
Retelling a Biblical story in modern day is all right, but it’s likely to fall flat since the audience may know the story and therefore is already anticipating the next steps and the ending. Those who don’t know the Biblical story will possibly be confused.
There are not many stories where a Christian is placed in a hard place with difficult obstacles and uses leading by Holy Spirit with ingenious solution. Write those stories and you’ll have a great number of people interested and engaged in the story.