Jim is always considerate and helpful towards Huck. We see this throughout the novel, and then Huck suddenly remembers all the good things Jim has done for him at the crucial moment when he is about to betray him by letting Miss Watson know where he is. He remembers how affectionate Jim has always been towards him during their journey down river and the way he always looked out for him, for example staying up all night to watch and letting him sleep. He remembers, too, how grieved Jim was whenever they happened to get separated during the journey, and how overjoyed he was whenthey met up again. Huck suddenly realises that Jim has been a true and devoted friend.This leads to the climactic moment of the entire novel, when Huck once and for all decides to stick by Jim, no matter what the consequences might be.