First, I think that the theme of this short story is that different people are different, no matter how much they like one another. In the story, the two men were like brothers and grew up in the same context doing the same things. But Jimmy went on to become a policeman and Bob a criminal.
The point of view in the story is that of a third party narrator, but one who does not see what is in the characters' thoughts -- they speak for themselves.
To me, the point of view in the story helps to reveal the theme because it does not give us any clues as to how the story will end. We are forced to try to figure out for ourselves what is going on. If the narrator were omniscient, we would know more about the characters and the suspense would be lost.