Here is a famous section of the Book of Mormon. God anticipates the arrogant presumption of many who think the Bible is the entire sum total of everything God intends to reveal. Because this would be the fundamental belief of many churches, they would react to the Book of Mormon as though it were blasphemy to suggest that God had a whole dispensation of his gospel among the Nephites in America, entirely separate from the people in the Holy Land. They would say, "A Bible, a Bible. We have got a Bible and there cannot be any more Bible." Of course when the Book of Mormon was first published, this declaration came pouring down from a thousand pulpits. Indeed they did cry out, "A Bible, a Bible. We have got a Bible and there cannot be any more Bible."
But God fires a strong rebuke against these Gentiles. Here they are boasting about having the Bible but have they ever thanked the Jews for the Bible? They wouldn't have any Bible if it weren't for the Jews. And have the Gentiles been grateful to the Jews for this sacred record? No, they have not. They have driven the Jews, persecuted the Jesus, and put thousands of them in gas chambers. How dare they boast about having a Bible when they have done all these things to the people who gave them the Bible!