It could be that as the literary landscape changes, Christian fiction is evolving and borrowing from other genres, thus appearing less Christian. Another factor could be that authors are exploring more complex and diverse themes that don't strictly adhere to traditional Christian concepts.
Diann Hunt is indeed a Christian fiction writer. Her stories often incorporate elements of faith, hope, and redemption, appealing to readers seeking spiritual and uplifting narratives.
Sure, Catherine Palmer is known for being a Christian fiction writer. Her books frequently explore Christian beliefs and their impact on the lives of her characters, which has endeared her to many readers of this specific literary category.
I'm not sure specifically which 'Livingston' is known as a writer of Christian novels. There could be many authors with that name. It would be helpful to have more context or to check in specialized Christian literature databases or libraries.
Christian writer novels frequently use religious symbolism. Take 'The Lion, the Witch and the Wardrobe' from 'The Chronicles of Narnia'. Aslan's sacrifice is a clear symbol of Jesus' sacrifice on the cross. They also tend to have characters that are on a journey of spiritual growth, just like the main character in 'Pilgrim's Progress' who is constantly learning and evolving in his faith.
Marilynne Robinson's writing doesn't strictly fall into the category of Christian fiction. Her novels delve into complex philosophical and social issues, going beyond the confines of religious-based storytelling.