Jonas explains that his interest in release stems from the fact that his father is releasing a twin that morning. The Giver wishes newchildren weren't released, then tells Jonas that as Receiver he can actually watch releases. In fact, The Giver says, if Jonas wants he can watch his father release the identical twin that morning. Jonas is nervous about spying on his father and also because The Giver seems so serious. Nevertheless, he agrees to watch.
The Giver understands that witnessing release is one of the final lessons Jonas must learn in his path toward wisdom. Jonas's decision to spy on his father marks a break with his family, the final tie connecting Jonas to the community. It's also a sign that Jonas is a true adult who can make his own choices.
The Giver turns on the video screen, and he and Jonas watch as Jonas's father weighs the two babies and then places the smaller one on a table. Jonas's father takes out a syringe and injects a needle into a vein on the newchild's forehead. The newchild jerks its muscles and then stops moving. Then Jonas's father says, "Bye bye," waves, puts the body into a carton, and sends it down a chute. Jonas realizes with horror that his father has killed the newchild—it twitched just as the dying man did on the battlefield. He realizes that "to be released" means to be killed.
Without memory, Jonas father can't understand the consequences of what he is doing. He doesn't understand the pain involved in death or the need to value individual life. He kills a healthy baby just because the rules say that he should. The weirdly childish way he acts after killing the baby, saying "bye bye," shows how little he understands his actions.
The Giver explains that this is why he was so sad when Rosemary was released. He tells Jonas that Rosemary actually asked to inject herself with the needle.
Rosemary's suicide was a way of escaping the community. But suicide is a cowardly and selfish, and does nothing to change the community.