Chris Jones is both and has written a novella called The Glass Ruins. Sez he:
In The Glass Ruins a man is sent from the future to present-day Seattle to convince his pregnant mother not to abort him.
Jasper Carnelian is a family man living in a post-collapse America with only the remnants of our current technology. Returning from an errand one night he is met by a mysterious man who supernaturally dispatches him to our present-day Seattle, with instructions only to find his young mother Annette. He soon realizes he is in a time before his birth, yet during his mother’s pregnancy with him.
The story alternates between Jasper’s trip to present-day Seattle and a time in the post-collapse future when Jasper is just ten years old.
In the present, he meets homeless men who discuss the failings of our world, lives through a bombing attack, and struggles to find his mother as a city falls into chaos.
In the future, Jasper questions a gas station owner on the origin of the universe, the big bang, and God.
You can read it for free here. He demonstrates once again Orson Scott Card’s remark that the only place in popular culture where you get to explore theological questions (that is, the really important questions that have preoccupied the human heart since the dawn of time) is in science fiction and fantasy. Everywhere else, clever people have decreed such matter verboten. This is called “freedom of thought”.