The son thanks his father politely, but feels inwardly disappointed. "The old man's got lots of money," he thinks to himself. "He really should have written me a fat check. Instead, he gives me this. The old tightwad!"
The son puts the Bible, still in its elegant presentation gift-box, on the upper shelf in his closet, and forgets about it.
He doesn't see his father very often after that, but every time he does, the father gives him sort of a strange look and asks him how he's enjoying reading the Bible he gave him. "Sure, Dad," replies the son on such occasions, "I'm enjoying it a lot."
It's only after the old man dies, when the son's been asked to read a Bible passage at his funeral, that he takes the book down and discovers his father had inserted a crisp, new hundred-dollar bill at the start of every biblical book.