Why did Rahim Khan summon Amir to Pakistan?

Amir now understood that Rahim Khan had called him to Peshawar to pay not only for his betrayal of Hassan, but for Baba's betrayal of Ali. Amir wondered if he was to blame for Hassan and Ali's deaths because he was the one who drove them out of the house and split up the family. Finally, at thirty-eight years old, Amir was ready to take responsibility for his actions. He returned to Rahim Khan's apartment to find him praying and told him he would bring Sohrab to Peshawar.