Francisco X Stork's books have Bible verses spoken by characters. Ex. Marcelo is interested in religion, so it fits. In another book, Irises, the father is a pastor so he will say something from the Bible. The daughters also think about what this means.
Even when characters are not going to church, I recognize a bit of a Bible verse that's used casually in many books. Ex. Do unto others ...; Truth will set you free; Judge not ...; etc. I see verses esp. in regard to social justice issues: welcome the foreigner, feed the poor, etc.