Some favorite Christian authors.
Dee Henderson- her series
Shaunti Feldman- Veritas Conflict
G.P. Taylor _ Shadowmancer and Wormwood
Frank Perretti- any book but especially The Visitation
Randy Alcorn
C.S. Lewis
Walter Wagerin > Book of Dun Cow.
I've read CS Lewis. I like science fiction, but most of it is Gaia-worship, capitalism bashing, evil Christians or atheists in space. Christian sci-fi seems a contradiction, but it doesn't have to be.
I like Tamara Wilhite's writings, but she only has one book thus far.
Go to the web site for Tyndale House Publishers or Bethany House Publishers. Both produce good, quality Christian Fiction. I was in Christian Book Sales for 25 years, You can depend on the material they produce.