Dr. Seamus Martinez is one of the galaxy's foremost experts in xenolinguistics - the study of extraterrestrial languages. He knows very well that in contact situations with aliens, the words you choose are of vital importance, and can have disastrous consequences. In fact, he's been sentenced to jail because of it.
He gets a shot at redemption when he is called upon to code-crack an alien religious language. He soon discovers, however, that deciphering languages is easy... it's navigating an alien species' entire belief system that's hard.