The novel's opening statement "It was the best of times, it was the worst of times" sets the tone for a story in which a given curcumstance is perceived as good or bad depending upon the point of view. Jerry Cruncher, for instance, considers his nocturnal occupation a viable source of income to provide for his hungry family but Mr. Lorry views it as an abhorrent practice worthy of censure. Under scrutiny Cruncher admits that the sights of the bloody revolution in Paris have convinced him that such an occupation is immoral and he resolves to give up the practice. The revolution itself is believed to be an abomination by the exiled aristocrats that meet at Tellson's whereas the peasantry, personified by the mender of roads and the woodsawyer, see it as an opportunity for empowerment and revenge. Most significantly, Doctor Manette's Bastille manuscript reveals that during his years in prison the doctor believed that the whole Evremonde clan should be destroyed but when his daughter has wedded an Evremonde he is resolute in his determination to save him. The litany of wrongs suffered by the French peasants including the horrible execution of Gaspard serves to create sympathy for events such as the storming of the Bastille. After the revolution turns bloody, however, the reader's sympathies are transferred to the doomed aristocrats awaiting execution.
The overarching theme of the novel is the struggle between those who have power and privilege and those who do not. At the beginning of the story, the French aristocrats exercise complete and more-or-less unfettered freedom to persecute and deprive those of the lower classes. This fact is harshly illustrated in Doctor Manette's prison manuscript which details how one of the Evremonde brothers utilized his medieval privilege of harnessing a vassal to a cart and driving him like an animal to his death. It is also shown by Jerry Cruncher's insistence that the strict and violent sentence of quartering is "barbarous" and being told by the sanctimonious bank clerk that the law is just simply because it exists. Later, when the tables have turned, it is the peasants who use their newly discovered power to harshly persecute the aristocrats through mass executions and imprisonment. Darnay notes when he is first interred in La Force prison that the rough looking men are in charge and the prisoners are polite and civil. Jerry Cruncher is deeply affected by the revolution and he more than any other English character in the novel would have reason to be inspired by the uprising of the French poor. But as a good Englishman, his avowal that its bloody sights have caused him to reconsider his grave robbing occupation indicates that he, at least, recognizes the futility in avenging violence with violence.
The novel's theme of self-sacrifice is best exemplified in the character of Sydney Carton whose willingness to give his own life for Lucie's happiness creates the means for Charles Darnay's salvation. He makes this willingness known well before the dangers of the revolution overtake the family when he says to Lucie: "If my career were of that bettter kindd that there was any opportunity or capacity of sacrifice in it, I would embrace any sacrifice for you and for those dear to you" (149). This theme is furthered by the seamstress who accompanies Carton to the Guillotine who hopes that by her death her cousin, a long-suffering member of the peasant class, will profit by the bloody revolution. Charles Darnay is willing to sacrifice his own happienss when he returns to France in an attempt to save the life of his former servant. Furthermore, Doctor Manette is shown to sacrifice his own mental health when he suffers a relapse of his prison-born derangement by allowing the nephew of his nemesis to marry his daughter.
As in many of Dickens' stories, prisons figure prominently in this novel. Imprisonment's ill effects upon the health of inmates is shown in Doctor Manette's mental illness and the pitiful state of shoemaking labor he is reduced to in order to survive. The oppressiveness of penal time is illustrated in the litany of "eighteen years" that Mr. Lorry dreams before retrieving the doctor, the count of the brutally tortured woman who lies bound and repeats her 12 count monologue until her death, and Charles Darnay's marking the hours by the chimes of the church bell. Dickens' descriptions of the harsh punishments given for minor offenses in both France and England connects the two regimes and serves as an implicit warning to Dickens' fellow countrymen that a bloody revolution is the result of wrongs done in the name of the people. The clerk at Tellson's fails to appreciate this relationship when Jerry offers his opinion that the punishment of quartering is "barbarous" and the clerk, echoing the sentiments of his government, he advises Jerry to "leave the law to take of itself". The clerk's matter-of-fact observation that "We all have our various ways of gaining a livelihood. Some of us have damp ways and some of us have dry ways" (57) reveals that the clerk has not considered that those whose ways are damp, and illegal, would want to change the prevailing mode of punishment.