The exposition of Hosseini's novel stresses the idea that there is a “way to be good again.” Through such an invocation, it is clear that the nature of betrayal in a character's act possesses a great deal of meaning to the entirety of the work. The nature of betrayal guides the work. Amir's betrayal of Hassan represents the point where the "way to be good again" holds allure over him. As a result, the reality of betrayal guides the work from its opening.
The novel's opening establishes that Amir's betrayal of Hassan ends up defining meaning within it. It is significant because this betrayal haunts at Amir, pulling and tugging at him. Amir cannot overcome the fact that he betrayed Hassan in his moment of desperation. When Assef and the bullies assault Hassan, Amir knows what happened and is convinced that Hassan knows Amir knew. In this moment of desperation and pain, Amir does nothing. When Amir frames Hassan for stealing the money, it is another instant in which betrayal in a single character contributes to the meaning of the work as a whole. This idea is reinforced throughout the narrative: "It may be unfair, but what happens in a few days, sometimes even a single day, can change the course of a whole lifetime...” The idea here is that individual actions, in particular acts of betrayal, contribute to meaning in life constitutes a large sense of meaning in the work. These actions define the individual and define both the work's narrative focus and Amir's life in a significant manner. As a result of betraying Hassan, Amir spends the majority of the narrative seeking to find a "way to be good again."
The nature of betrayal strikes at the heart of Amir's narrative. The idea that one must atone for the act of betrayal is significant to the work as a whole: "There is only one sin. and that is theft... when you tell a lie, you steal someones right to the truth.” The acknowledgement of a wrong having been done and the need to make it right is what motivates Amir to go back to Afghanistan. This shows how the act of betrayal contributes to the meaning of the work as a whole. Characters like Amir seek to be "good again" as a result of previous acts of betrayal. In having to go back to Afghanistan, driving the plot in going back to what once was, the betrayal in the actions of a single character contributes to the meaning of the work, as a whole.
Finally, when Amir adopts Sohrab, it is a reminder of how the nature of betrayal in an character contributes to the meaning of the work as a whole. Adopting Sohrab, Hassan's son, is a way for Amir to become "good again." It is a way for him to be able to make right that which was wrong. It is a means for him to atone for his betrayal. In saving Amir's son and committing to him "a thousand times over," even in chasing down his kites like his father did for him, it is clear that the act of betrayal contributes to the meaning of the work as a whole. The narrative's ending is one where Amir has found his path to "become good again." He has decided to commit his life to Sohrab, in much the same way that Hassan did for Amir. In this light, one sees how the act of betrayal weighed on Hassan to the point where it became a means for his own redemption. It is here in which the act of betrayal contributes to the meaning of the work as a whole because it provides the path towards restoration and hope in a world devoid of it.