Fear. Everybody has it. The only variables are 1) what makes us afraid and 2) how we respond to that fear. Snakes scare me, but some fortunate people are unphased by them. By the same token, insects don't scare me at all, but I know some people find them terrifying.
With "Phobos," I wanted to do a play on words. On the one hand, it refers to its setting, the Martian moon of (yeah, you guessed it) Phobos. But I also felt that the only natural direction for a story with such a title, with such a setting, would be one dealing with fear. Since human psychology covers a wide range of fears and phobias, I had a lot to choose from. In dealing with the personal phobia of my protagonist, Travis Lyle, I decided that it would be too easy to pick something like snakes or spiders, or even something less tangible but more common, like acrophobia (heights) or claustrophobia. I prayed that God would lead me to something that wasn't that obvious but that could still support a story. So, after doing some research into phobias, I stumbled across something suitably subtle, and then the story grew quickly from there. Prayer answered.
So what does "spiriutal suspense" have to do with a story about fear? The Bible tells us 365 times (yep, one for each day of the year) to "Fear not." Fear is normal, but those of us who are Christians can place our faith and trust in God, who is bigger than whatever scares us. He never leaves us, nor does he forsake us. He is with us no matter what. Because of that truth, we can overcome our fears. We can trust in Him to hold us up even as we face what scares us.