The story is a fantasy-allegory portraying the critical condition of religion in the modern world. The explorer, representing the humanitarian outlook of a secularist culture, visits an earth that is in a state of sin. The old commandant created and organized the penal colony and invented its dreadful machinery of justice/injustice—call him the god of an authoritarian faith. Somehow he lost his hold over the colony, but one day he may return and reclaim it. Meanwhile his fanatic disciple, the officer, serves the colony as its police officer, judge, and executioner.

What the explorer must choose on this island is either morality or spirituality, for Kafka regards the two as having suffered schism. The Old Order is revoltingly sadistic, but, according to the officer’s testimony, it does offer humankind redemption through an agonizing ritual of pain. “How we all absorbed the look of transfiguration on the face of the sufferer,” exults the officer. “What times these were, my comrade!” Nevertheless, the explorer has no difficulty condemning the Old Order’s inquisitorial severity: “The injustice of the procedure and the inhumanity of the execution were undeniable.”

The New Order is humane, sentimental, and concerned with the colony’s economic and political recovery. It allows the machine to fall into disrepair while improving the island’s harbor installations. The New Order, however, lacks the strength of conviction to confront the practices of the Old Order directly and abolish them outright. It is slack, shallow, and worldly, unable to offer humanity more than palliatives and fleshly indulgences. The new commandant immerses himself in a sea of admiring women, who weaken the law’s rigor through erotic enticements.

The victory that the New Order achieves over the Old Order is therefore unredemptive and pyrrhic. The explorer, while convinced of the Old Order’s injustice, is also careful to keep his distance from the new dispensation’s slovenly ways. He admires the officer’s dedication to his faith and willingness to martyr himself to the machine. “If the judicial procedure which the officer cherished were really so near its end . . . then the officer was doing the right thing; in his place the explorer would not have acted otherwise.” Unlike the officer, the explorer is adrift in a sea of aimless, situational ethics, anchored to no absolute standard, trained only in rational positivism.

Why does the machine execute the officer and in the process commit suicide? Possibly because the injunction it is asked to write—“BE JUST!”—contradicts the despotic nature of the Old Order and therefore violates the nature of the machine’s tyranny. In the hour of its self-destruction, the machine becomes animated as a horrifying monster that shows its teeth as it jabs the officer’s body and drives its iron spike into his forehead, murdering him without granting him absolution or transcendence. Like the hunter Gracchus in Kafka’s later sketch by that title, the dead man remains earthbound and unredeemed.

The story’s conclusion has puzzled many readers. Because the explorer has denounced the Old Order as inhumane for its cruel treatment of the soldier-prisoner, he might be expected to exhibit his own humaneness by taking the freed man aboard his boat as he leaves the island. Instead, he threatens him with a heavy rope to prevent him “from attempting the leap.” Perhaps Kafka means to have the explorer show his contempt for the condemned man’s previously demonstrated refusal to extricate the officer from the machine’s harrowing needles. In effect, the explorer enacts the adage, “A plague on both your houses!” In allowing the explorer to escape the colony, Kafka also allows him to evade a meaningful choice between a purposeful but blood-drenched religion and a purposeless but humane secularism.

Justice and Injustice
The story concerns the administration of justice in a penal colony. A time has recently passed when the operation of the colony's judicial system received popular support and approval. But this approval was gained by the popularity of the architect of the justice system and the execution machine, the Commandant. The new Commandant shows no enthusiasm for his predecessor's social order. Rather than trying to actively reform the system, it appears he is hoping to change things through benign neglect. In the meantime the old judicial system still operates, thanks to the dedication of the old Commandant's assistant, an officer who sees it as his duty to preserve the machine which inflicts the same fatal punishment on all who are charged, regardless of their crime. The colony's judicial system does not recognize the concept of injustice. Prisoners are not allowed to defend themselves. They are accused by word of mouth—in the case of the condemned man in the story, by his superior officer—and then executed without a judicial hearing or any chance to defend themselves. It is significant, and an example of irony, that when the guardian of the machine gives up his own life at the end of the story, the sentence which was supposed to have been inscribed on his body, had the machine worked properly, was "BE JUST."

Guilt and Innocence
The officer who oversees the execution machine considers one of the main merits of the colony's judicial system to be the fact that guilt is never questioned. "My guiding principle is this: Guilt is never to be doubted. Other courts cannot follow that principle, for they consist of several opinions and have higher courts to scrutinize them. This is not the case here." If the story were merely about the methods of dealing with isolated acts of criminal behavior—petty theft, for example—the plot could be read as an exaggerated comment on the harsh and inhumane punitive methods of fundamentalist systems of law. However, the condemned man's crime is a fairly minor one: he fell asleep on duty and shouted back at his captain. His death sentence suggests that a point is being made about the inherent sinfulness of human nature. The execution machine becomes a symbol for the judgment that all people must eventually face. Due to the machine's twelve-hour cycle, victims become conscious of their sinfulness before the end comes. Guilt is written on the body while the body clings to life, and in the time remaining the prisoner must face his loss of innocence.

Punishment
Another feature of the colony's judicial system is that there is no gradation of punishment. The punishment—death—is the same no matter what the crime, except in one regard. The Harrow's needles inscribe a different sentence on the body of each condemned person. The words compose both a linguistic sentence (a series of words) and a penal sentence (the condemned person's punishment). This sentence is programmed into the machine at the start of the execution process by the operating officer. The prisoner is not told what it is before the machine is switched on. "He'll learn it on his body." The sentence is directly related to whichever commandment has been broken. Readers are given two examples. The prisoner who fell asleep on duty and shouted at his captain "will have written on his body: HONOR THY SUPERIORS!'' The officer, in a bizarre act of sudden self-condemnation, selects his own sentence: "BE JUST."

Choices and Consequences
The explorer and the officer are the only characters in the story who act decisively, in accordance with their own beliefs. The soldier and the condemned man are submissive and merely play the roles assigned to them by the judicial process. They make a half-hearted attempt to take control of their lives at the end of the story, but they do not strongly assert their desire to leave the colony enough to make it happen. The explorer, as an outsider, is placed in the position of critical commentator. He knows this, and likewise the officer seeks his help because he sees the explorer's presence as one more ploy of the new Commandant in his efforts to destabilize the old order. The explorer's Western European background is repeatedly emphasized. The explorer chooses to declare his position to the officer, but also chooses not to report his views to the new Commandant. The officer, realizing that even without a formal and public declaration of criticism from the explorer that his efforts to prop up the old system of justice are doomed to failure. In light of this, he chooses to accept the consequences of his own system and throws himself at the mercy of the machine.

Science and Technology
The execution machine is a grotesque torture apparatus. Its workings are described in great detail in the story. Though it is not highly technical, it emphasizes the mechanical, no-room-for-error nature of the punishment process, as meted out by its operator, the officer. The explorer, who comes from a more enlightened background, seems at first uninterested in the machine. The officer, so proud of the old Commandant's invention, is apparently unaware that the machine, although horrifically efficient in its execution, is also comically grotesque. It is like the brain-child of a mad professor, as might be found in a traditional horror story, and Kafka provides it with the conventional demise for such machines. It breaks apart while in the process of dispatching its last victim, possibly symbolizing humankind's misplaced reliance on machines to perform perfectly. At the end of the story the explorer leaves the island by rowing to his steamer, another technical invention of the modern age, but one without the punitive overtones of the killing machine.