A Quote from a book that you can't forget?

I've read The Mortal Instruments almost 10 years ago. And I can't forget these lines from Clary and Jace in City of Ashes.

"Do you believe in God?"

“There might be a God, Clary, and there might not. But I don’t think it matters. Either way, we’re on our own.”

I don't know why, maybe because the story is based/inspired from my religion. And being a citizen of a religious country, a teenager at that, I was shocked when Clary asked if Jace believed in God. Because here, there's no "not believing in God". Atheists here are not welcomed. It's just refreshing to see that question, that you cannot ask in the open here. Maybe that's why it was engraved on me, even after 10 years.