In Conrad's story, The Secret Sharer, comparing Leggatt to Cain is appropriate, for like Cain, Leggatt has killed his "brother," a fellow ship mate on the Sephora. And like Cain, Leggatt is forced to wander the earth as an outcast of his society. But one should recall that Cain was not simply punished by God, he was also placed under God's divine protection...
"whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the Lord set a mark upon Cain, lest any finding him should kill him."
Why is this? Why should God, who is the ultimate judge of all creation, extend his protection to Cain, who murdered his own brother? In this respect, the Captain who gives sanctuary to Leggatt, has done nothing more than extend God's protection to another human being, just as churches have done throughout the ages (hence, the original meaning of "sanctuary"). So, we find two opposing forces at work in Conrad's story: the justice of man, represented by Captain Archbold, and the justice of God, which in this case is represented by a young captain whose name is unknown to us (cf. "Yahweh" literally, he who is without name).
Although his name is unknown, we know something of his character. He is not afraid to shelter a stranger, though at some risk to himself. He undertakes a bold, dangerous passage near an island which his crew believes will lead to their death. Yet, in this crisis he does not waver but shows a firm command of his ship, unlike Captain Archbold who was apparently unable to save his own ship from disaster.
Then again, unlike the story from Genesis, the man killed by Leggatt was not Abel. Instead, he ...
"... was one of those creatures that are just simmering all the time
with a silly sort of wickedness. Miserable devils that have no business
to live at all. He wouldn't do his duty and wouldn't let anybody else do
theirs."
So, what is our duty? At sea, when caught in a storm, a sailor's first duty is to survive, and toward that end the captain must decide how to achieve that purpose. But Captain Archbold (like Captain Queeg in the Caine Mutiny) could not handle the crisis, so it was up to Leggatt to act. We learn that one of the crew endangered the survival of the Sephora, and at that dire moment, Leggatt reacted violently and killed the man. We recall that Cain's anger at his brother was motivated by jealousy, yet Leggatt's anger was brought on by a struggle to save his own ship from capsizing. With these extenuating circumstances in mind, perhaps a maritime trial would result in a lenient verdict for Leggatt. But perhaps not. In any case, he doesn't wait around to see.
The only trial that occurs happens in the mind and soul of the captain who shelters Leggatt. Conrad's story concerns the moral consequences of this action. The captain sees Leggatt as a kind of alter ego of himself. Not to say that Leggatt is an evil twin of what he, the captain, might have become. For he sees Leggatt as a man falsely accused...
"He appealed to me as if our experiences had been as identical as
our clothes. And I knew well enough the pestiferous danger of such a
character where there are no means of legal repression. And I knew well
enough also that my double there was no homicidal ruffian."
Justice at sea is different from the kind that normally prevails on land. A vessel at sea is a miniature society alone to itself, with its own rules and traditions. The captain is invested with godlike power over life and death. His word is law. For the crew, he is the only judge and jury that matters. While for the captain, the crew's loyalty to him rests on their belief in his competence and on the authority he displays in the performance of his duties. For a young, untested captain, a maiden voyage is often the initiation which determines how his maritime career will unfold. Either he proves his worth as the captain of his ship, or he does not. If he fails, no crew will ever entrust him again with either their lives or their fortune.
In Conrad's story, the young captain is a stranger to his crew. His appointment to the ship happened suddenly, with no opportunity to prove himself to the men who must serve under him. Then Leggatt appears out of the night, clinging to the ladder of his ship. Once he is aboard, the captain must decide quickly whether to hide Leggatt from the crew, or return him to the Sephora to face his accusers. He is not sure what to do. Either Leggatt is lying, in which case the captain is protecting a murderer (and risking his career); or he is innocent of murder, and sending him back may well result in an unfair punishment. Sometimes truth is difficult to apprehend. In the end, the captain decides to trust his own judgment regarding Leggatt's innocence. Was he right to do so?
It all depends on whose testimony you believe...Captain Archbold or Leggatt. At the end of Conrad's story, the young captain demonstrates his authority and his courage by sailing his ship into harm's way, allowing Leggatt to escape. He succeeds in bringing his ship through unscathed. But even a man of ability needs a little luck. And Leggatt the murderer, if that is what he is, becomes the means by which the captain, who was indeed a "stranger to himself" comes into full awareness of his power to command his ship, and the moral burden which that duty entails.
We recall that God allows Cain to go forth into the world after murdering Abel, though his reasons for doing so are mysterious. Perhaps God puts a mark on Cain to remind us that the power of life and death belongs to God alone. Cain becomes a nomadic witness, reminding us of who really is in charge of things. But since Leggatt carries no mark (the captain's hat was discarded as Leggatt jumped overboard), he can't really witness to anything but his own survival. On the other hand, perhaps Cain (Leggatt) goes forth as a testament to God's unlimited power of grace, and the possibility for redemption that lives within us all. Thus, the secret of our own guilt or innocence can only be shared with a stranger, and Conrad's story, like its protagonist's real identity, remains shrouded behind a veil of cosmic uncertainty.