In this scene, Dally is talking about Cherry Valance being their spy with Johnny and Ponyboy. Dally was talking about how she thinks the whole situation is her fault.
Inside The Burning Church
In Dally's car, all three of them talk about their parents and how Johnny's and Dally's don't care about them. They each get a little emotional about it and this causes Dally to get annoyed with them.
In The Ambulance
One of your friends smacked you on the back because you caught on fire
Ponyboy, Johnny and Dally drive up to the church and see it burning with a crowd in front. Johnny and Pony are frightened and feel that it was their fault and they hop out of the car before Dally could get them.
Johnny and Ponyboy took responsibility after they heard children yelling inside because of the fire they started. Pony starts placing the kids outside as the smoke starts to take over his lungs. When he finishes helping the kids, he jumps out the window and suddenly feels a hard slap across his back.
Forget those blasted kids!
After Ponyboy wakes up from the smoke in his lungs and the slap, he finds that he is in an ambulance with a local farmer named Jerry. Jerry tells Ponyboy about what happened and Pony starts to worry about Johnny and Dally.
When Ponyboy is talking to Jerry in the waiting room waiting for Johnny and Dally, SodaPop and Darry come in. Ponyboy sees them and immediately feels sorry that he ran away. Darry was so happy and relieved, he started to cry.