For beginners, 'The Lion, the Witch and the Wardrobe' from 'The Chronicles of Narnia' series is great. It's easy to read and the story of the children entering Narnia and the battle against the White Witch is exciting and full of Christian symbolism. Another good one is 'The Little Pilgrim's Progress' which is a simplified version of 'The Pilgrim's Progress' and gives a good introduction to the allegorical style and Christian teachings.
Beginner readers might like 'The Water Babies' by Charles Kingsley. It has elements of Christian morality in the story of a chimney sweep's journey to becoming a 'water baby' and his moral growth. 'Hinds' Feet on High Places' by Hannah Hurnard is also a good start. It's an allegorical tale about a character named Much - Afraid who goes on a journey of spiritual growth. The story is engaging and can introduce readers to basic Christian concepts in a simple yet profound way.
I would recommend 'A Christmas Carol' by Charles Dickens. It's a well - known story that has a strong Christian message about redemption and the spirit of giving. The transformation of Ebenezer Scrooge is a great example of how one can change for the better through the influence of Christian values. Also, 'The Story of the Other Wise Man' by Henry van Dyke is a short and sweet story that is accessible for beginners. It tells the story of a fourth wise man who also set out to find Jesus but had a different journey filled with acts of kindness and self - sacrifice.