Four of my favorite authors/thinkers on writing fantasy, and how it leads us to recognize God:
J.R.R. Tolkien called fantasy the most perfect art form and described Christ's birth, life, death and resurrection as "the greatest fairy tale of all. And wonder of wonders, it is true."
G. K. Chesterton said that fantasy reminds us that "the universe is wild and full of marvels... In the fairy tales the cosmos goes mad, but the hero does not go mad. In the modern novels the hero is mad before the book begins, and suffers from the harsh steadiness... of the cosmos."
C. S. Lewis observed, "It would be nice if no little boy... were ever at all frightened. But if he were going to be frightened, I think it would be better he should think of giants and dragons than merely of burglars."
George MacDonald: "If I can wake in any human heart just a little fluttering of life, if I can help any human soul to feel... that there is an eternal world, a world of life, of truth; a world of duty, of hope, of infinite joy... If I can make the clouds just part the least bit, and give a glimpse of the blue sky, of the infinite realities of things, then I hold that it is worth doing."