In the novel The Outsiders, what was learned and what was the effect that was important to Johnny and Ponyboy?

The Outsiders is a coming of age story in which Ponyboy develops perspective on life and significantly matures by the end of the novel. At the beginning of the story, Ponyboy is a relatively naive, immature adolescent, who believes that Darry does not love him and is unable to accurately judge and perceive Dally Winston. Pony also struggles to overcome the negative reputation attached to being a Greaser and laments the fact that society considers him lousy without understanding him. After Johnny kills Bob Sheldon in self-defense, the two boys are forced to hide out in an abandoned church in Windrixville, where they become even closer friends and rely on each other for support.
One morning, Ponyboy watches the sunrise with Johnny and recites the well-known Robert Frost poem "Nothing Gold Can Stay" but is unable to interpret its meaning. Later on, the boys return to their hideout after eating with Dally, only to discover that the church is on fire and children are trapped inside. Ponyboy and Johnny proceed to run into the burning building and save each child. Tragically, Johnny is mortally wounded during the event and is placed in critical condition. At the hospital, Ponyboy sees Darry crying and finally understands that he truly loves him. Following the big rumble, Johnny dies and Dally loses his mind. Ponyboy ends up witnessing Johnny and Dally's deaths and is severely traumatized by the experience.
Eventually, Ponyboy discovers a letter Johnny wrote to him before he passed away, which elaborates on the Robert Frost poem and encourages him to remain innocent and hopeful ("Stay gold"). After reading Johnny's letter, Ponyboy experiences a dramatic transformation and realizes that it is important to share his story with other adolescents who are considered outsiders. He repairs his relationship with Darry and understands the importance of never losing hope or his childhood innocence. Both Johnny and Ponyboy learn the importance of remaining "gold" and holding onto the pure elements of life despite their surrounding environment.