It examines religion through the eyes of a Christian reformer who is corrupted by a Swedish cruise ship hostess (and loves every minute of it). Enduring a series of world-changes brought about by a petulant god Jehovah, the reformer and his mistress work their way from Mexico to Kansas as dishwasher and waitress. They enjoy the Texas hospitality of Satan himself, but are separated by the Rapture (pagans don't go to heaven).
Heinlein's vivid depiction of a Heaven ruled by snotty angels and a Hell where everyone has a wonderful time--with Mary Magdalene shuttling breezily between both places--is a brilliant, biting satire on American evangelical Christianity.
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