In the book "The Kite Runner" years before Amir has the confrontation with Assef, Amir witnesses Assef raping his close companion Hassan. He has always been skittish and is not a fighter. He is worried about the destruction of his kite but he is also scared to try and intervene. He never tells what he knows and it causes his feelings to turn into anger towards Hassan. He begins to treat the boy badly. The boy has done nothing but love Amir and still cares about him. Amir tries to get his father to send Ali and Hassan away. When his father doesn't, he sets Hassan up by placing an object where it appears that Hassan stole it. Ali leaves with Hassan.
Amir has spent his life suffering inside because of the events on that day and the way that he had handled things. After Rahim tells him about Hassan and his wife's death Amir goes to find Sohrab, Hassan's son. He has found out that Hassan was actually his half brother. He risks his life to find the boy and wears a fake beard. However, he does not know that the boy is being held by Assef.
Assef is Hassan's rapeist and he is a saddist. He has turned the boy, Sorhab, into a sexual toy. He makes him dress like a girl and ouches him in front of Amir. He remembers that Amir was always afraid and he plays with his mind. Amir attacks him as soon as they are alone and rescues Sohrab.
Amir’s scar represents his taking a stand. His father was one to state many quotes. One of the quotes in the book was:
“A boy who won’t stand up for himself becomes a man who can’t stand up to anything.”
Amir is no longer the boy who would not stand up. He is now the man who stood up to save his brother’s child. The scar is his symbol of manhood.
The situation with Assef sets Amir free from the shame he had been holding since his childhood. His redemption occurs when he ahs saved the boy and is raising him with pride. The boy is known as a Hazara but he is no longer that, he is Amir’s nephew.