"10 Science Fiction Books Featuring Interplanetary Religious Missions" by Ceridwen Christensen (Barnes & Noble).
...Science fiction allows us to walk around historical events and people, play them out with different parameters and in extremis. The religious mission—with or without contact—transposed into the stars provides ample room in which to shape a story. Depending on the religion in question, the mission can be naïve or pious, compassionate or conquering, or a mixture of all of these attributes. The generation ship, the definitive long-haul interstellar vessel in universes without faster than light travel, is another place writers can play out the inevitable conclusions of a theology, for better or for worse—or both at once.
Here are 10 novels that detail religious missions to the stars—plus one bonus fantasy excursion. (Note: I'm not including novels about missions that feature religious members, but aren't otherwise organized around religious principles.)