"Stay gold, Ponyboy. Stay golden..." Those were the last words Johnny would say in his life.
This quote is important because Johnny knew Ponyboy loved his mother very much and earlier Ponyboy had used the word golden to describe his mother. When Ponyboys says that his mother was golden what I think that it was used as a word showing many wonderful qualities she had. Some of those things might include: intelligence, beauty, humor and kindness.