The Heart of Midlothian Themes
As suggested above, the moral dilemma that faces Jeanie Deans, and with which she deals successfully, is at the core of the novel. Even when Effie begs her sister to lie for her, to save her life (child murder was a capital crime), Jeanie remains firmly attached to her highly moral upbringing. She adheres to what she sees as a higher morality than sisterly love; her principal love is for God, whom she will not betray, even for her own flesh and blood. This rigidity of conscience results from the childhood that Jeanie has spent in the home of her Covenanter father, David Deans. Therefore, the attitude that she reveals is not only believable, but inevitable. Her journey to London to free Effie is not only heroic, it is of-a-piece with Jeanie's firm principles: she has refused to "save" her sister, so she must do all that she can to prevent Effie's execution.
Throughout the story, Jeanie's high moral code (and that of her husband-to-be, Reuben Butler, a minister, appropriately) shines a thematic light on the events and the other characters in the novel. A related thematic thread is the need for truth, in order to live a happy and meaningful life. As the truth helps Jeanie to retain her self-respect and sense of self-worth, the lack of truth (or the twisting of it) brings misery to Effie, George, and many of their cohorts. Madge is one striking example; she helped to spirit away the baby that Effie bore. Robertson/Staunton not only tells lies; he lives one for a long time. His death at the end of the book can be viewed as more than poetic justice; it may be judged as profound moral justice.
The contrast between George and Jeanie is thematically and dramatically effective: George dies in a fight, and Jeanie finds happiness married to Reuben. She has been a heroine indeed, as her father says upon her return from London: "Jeanie—my ain Jeanie—my best—my most dutiful bairn [child]... I am hardly worthy of thee! Thou hast redeemed... the honour of our house—Bless thee, my bairn, with mercies promised and purchased! But He has blessed thee, in the good of which He has made thee the instrument." In the same way, Scott has made Jeanie his instrument to send forth his message about morality in general and truth in particular.