Part I, Chapter 1.2, the mysterious stranger's words to Bob Shane
Lightning (1988)
Quotes from book
Lightning

Lightning is a novel by American writer Dean Koontz, released in 1988. A 2003 reprinting includes a new afterword by the author, discussing editorial politics.
"If you don't know," she said, "maybe I should be the one asking the questions here."
Part I, Chapter 2.10, dialog between 12-year-old Laura Shane and a psychotherapist after the death of her foster mother
Lightning (1988)
Part II, Chapter 5.4; 8-year-old Chris considering the time-travellers' strategy for catching them
Lightning (1988)
“A fanatic is a nut who has something to believe in.”
Part II, Chapter 6.4; Laura's explanation to Chris
Lightning (1988)
Part II, Chapter 5.1; conversation between Laura and her son Chris
Lightning (1988)