Christian Allegory
The entire movie is a very tightly constructed allegory of Christianity. Klaatu is a messenger of peace backed by an agent of wrath who arrives from the heavens to preach a gospel that unless mankind learns to love their terrestrial neighbors, they will have no place in the unknown realm in the cosmos.
Mr. Carpenter
After being shot the first time, Klaatu has his wounds attended to at a hospital from which he escapes in order live among people so that he might become “familiar with the basis for [their strange, unreasoning attitudes.” In doing so, he adopts a name found on a dry cleaning label: Carpenter. The symbolism of this name clearly connects him quite explicitly as a Christ figure.
The Wrath of Gort
Among the other alterations to the character made in the transition from the original short story to the film adaptation is a name change. What was Gnut in the story becomes Gort in the film. Say both out loud and determine for yourself which one sounds more like “God.” Gort is the allegory's symbol of Old Testament style wrath of God.
Helen of Magdalen
Helen Benson is a widow with a son. That’s about as close as a 1951 flying saucer movie was going to get to a portrayal of the traditional view of Mary Magdalene as a prostitute. The symbolism all points to this connection, however: it is Helen who is Klaatu’s closest acolyte and to whom he reveals his secrets. Most importantly, it is Helen who has the faith to believe Klaatu and save the world from the wrath of Gort.
“Klaatu Barada Nikto”
One of the great film mysteries of all time is what, exactly, does the phrase that Klaatu tells Helen is the only means of stopping Gort’s destruction should something happen to him actually mean. Many have spent much time trying to find some connection to an existing language, both dead and alive while one of the cast members is on record as assuming it can only mean “save Earth.” Within the construction of the film’s Christian allegory, however, the general concept of the meaning seems clear enough. Klaatu tells Helen that the phrase it he only way to “save Earth” but he doesn’t clarify exactly what it means. The result of this ambiguity implies that Helen—at the single most critical moment in the history of mankind—must go on faith that Klaatu has told her the truth when actually—for all she really knows—it could just as well be a coded message that reinforces Gort’s power or even brings on more powerful robots. That Klaatu’s name is part of the message is also a clue that it is not just a message about Gort or stopping his rampage. All these aspects converge to strongly imply within the allegorical structure that “Klaatu barada nikto” is a symbol of simple prayerful benediction along the lines of “Jesus is love” that proves to Gort that a person of faith has been found.
