As we grow older we develop our own moral code based on our experiences.
Jonas has to learn how to think for himself. This is something that we all go through. During the book, Jonas goes from blindly accepting everything he has been told to questioning everything he has ever believed. Although his is an extreme example, the process of growing up still involves shedding delusions in his world and in ours.
Let’s take as an example the release of newchildren. At the beginning of the story, Jonas barely thinks twice about it.
Release of newchildren was always sad, because they hadn't had a chance to enjoy life within the community yet. And they hadn't done anything wrong. (Ch. 1)
Jonas is aware that there is something not good about releasing a baby, but he is not really paying attention. Release is common in the community, but no one talks about what it really means and most people do not know.
Jonas learns the hard way what release means. As he receives the memories throughout his training, he starts to feel and have human emotions. Most people in his community do not feel anything, or at least not anything serious. This allows him to have a reaction, a strong reaction, to watching his father kill the baby.
When Jonas sees his father’s release of the newborn twin, he suddenly realizes that release is wrong. He is horrified to see his father murder the baby, and he starts to understand the undying devotion to rules and order has had a hazardous effect on his community.
"I said it because it's true. It's the way they live. It's the life that was created for them. It's the same life that you would have, if you had not been chosen as my successor."
"But he lied to me!" Jonas wept. (Ch. 20)
Jonas is upset because he has finally developed his own moral code. It contradicts the one he has been taught all of his life. His people value sameness and obedience, but Jonas learns that blind obedience can be immoral.
As we grow up, we have to assess what we have been taught and told and decide for ourselves if we believe it. This is part of coming of age, or becoming an adult. Like Jonas, you may have had to re-evaluate some of your deeply held beliefs as you got older. Sometimes they are perfectly acceptable. Other times, you may feel betrayed into believing something that is wrong.