When Jonas is selected as Receiver of Memory by the Committee of Elders during the Ceremony of Twelve, he is told that he was chosen for his special qualities. These are: intelligence, integrity, courage, wisdom, and the capacity to see beyond.
Jonas has shown “all of the qualities that a Receiver must have" (ch 8), but he needs to acquire wisdom. Since Jonas is an intelligent and thoughtful boy, the Elders are sure that he can develop wisdom through his training.
Integrity refers to the idea that Jonas has character. He is a good person. Courage is necessary for his role, because he will be venturing into the realm of memories. There will be great physical pain and mental anguish.
The capacity to see beyond is what makes Jonas unique. He is beginning to see color, when no one else in the community can.
"I think it's true," he told the Chief Elder and the community. "I don't understand it yet. I don't know what it is. But sometimes I see something. And maybe it's beyond." (ch 8, p. 64)
Because of these special qualities, Jonas is selected Receiver of Memory. Only one person at a time is able to take on this role, so it is a very important one. Jonas does not know it yet, but he is instrumental in keeping the community in sameness by holding the memories of the past, back and back and back. Witht the memories, his life is about to change forever. He will never look at the community the same way again.
Lowry, Lois (1993-04-26). The Giver (Newbery Medal Book). Houghton Mifflin Harcourt. Kindle Edition.