I was abruptly perturbed — and considerably puzzled, too. A blasphemy was, as had been impressed on me often enough, a frightful thing. Yet there was nothing frightful about Sophie. She was simply an ordinary little girl — if a great deal more sensible and brave than most. Yet according to the Definition… Clearly there must be a mistake somewhere.
-- David (chapter 1)

Importance: This quote shows David's first instance of disillusionment with the teachings of Waknuk. Although Sophie conforms to the idea of a Deviation, he cannot fathom her as a sin.

ONLY THE IMAGE OF GOD IS MAN. The one on the right: KEEP PURE THE STOCK OF THE LORD. On the opposite wall two more said: BLESSED IS THE NORM, and IN PURITY OUR SALVATION.
-- David (chapter 1)

Importance: These texts hanging on David's wall remind him to be vigilant about Deviations. He fears these texts, signalling that the idea of the True Image is suspect.

It...
-- David (chapter 4)