why does jonas think about his experience on the playing field after watching his father release the baby?

Jonas thinks about his experience on the playing field after watching his father release the baby because it was another instance of the community members not truly grasping the concept of death. His friends couldn’t understand that war was a serious matter because it involved suffering and death because they couldn’t understand why those were so bad, and his father couldn’t understand that the death of the baby just because it was slightly smaller than its twin was significant because he couldn’t understand the grave (pun unintended) significance of death. Jonas, however, can, as a result of his experiences of being a Receiver.