While his judgment was in suspense he was beset by horrible fears--the fear that he might be driven to do a villainous deed, the greater fear that he should not accomplish it, the awful fear, rising above all else in his mind, of seeing Josephine overtaken by the horrible fate which menaced her, and he himself still alive to feel her misery and his own.
No, rather than that he would himself kill the man.

It was not the part that had been assigned to him, but if she would not save herself it would be the noblest thing to do.

Was he to allow O'Shea, with a wife and children, to involve himself in such dire trouble, when he, who had no one dependent upon him, could do the deed, and take what consequences might be?
He felt a glow of moral worth like that which he had felt when he decided upon his mission to the island--greater, for in that his motives had been mixed and sordid, and in this his only object was to save lives that were of more worth than his own.

Should he kill the man, he would hardly escape death, and even if he did, he could never look Josephine in the face again.
Why not?
Why, if this deed were so good, could he not, after the doing of it, go back to her and read gratitude in her eyes?
Because Josephine's standard of right and wrong was different from his.

What was her standard?
His mind cried out an impatient answer.