How we cite our quotes: (Chapter.Paragraph)
Quote #1
I'll begin long before me, for no one should describe his life who lacks the patience to commemorate at least half his grandparents' existence before detailing his own (1.13).
We're not sure why Oskar wants to write his life story, but he recognizes that his personal history begins long before his birth. This is a pretty strong statement that we have to explore the past to understand ourselves.
Quote #2
[…] you helped them to know themselves. Many a respectable, elegant lady, many an upstanding uncle, […] would never have recognized the thief that dwells within had your voice not led them to steal, nor would they have undergone such change as citizens […] (10.25).
Most people succumbed to temptation as they passed the shop windows that Oskar broke open. Oskar wonders if it was his evilness that led them to temptation, but he concludes that it was their own nature. They were unaware of it until they did the stealing. Grass has said that many people believed they had been led in some shadowy way by Hitler into going along with the Nazi regime. He obviously doesn't buy that.
Quote #3
There were many who later said she cursed my presumptive father Matzerath and called him her daughter's murderer. There was also talk of my fall down the cellar steps. She took the tale over from Mama and never allowed Matzerath to forget his supposed guilt for my supposed accident (13.17).
Oskar's grandmother tries to make his father feel guilty by reminding him of the things he did that might have contributed to his mother's death. This is an example of how Grass describes the errors of memory—little Oskar threw himself down the steps; Matzerath had nothing to do with it, really. The adults constructed a different, and false, narrative based on what they saw.