When Mormons come to your door, they ask you to accept a copy of the Book of Mormon. You demur, saying you do not believe in its inspiration and so have little interest in reading it. Just give it a try, they say. See what you think of it. If you read a bit of it, you will realize that it is from God. How? Because you will receive a “burning in the bosom.” That will be your proof of the book’s bona fides. You will know that it is from God.
Catholic apologist Arnold Lunn had his own word for the same idea: “fif,” which stood for “funny internal feeling.” Without having Mormons particularly in mind, Lunn wrote about sectarians who sought to prove their case by claiming that God confirmed their position by giving inquirers an unmistakable and un-ignorable emotional or physical sensation. For many people, said Lunn, “fif” sufficed as proof.
It should not take much thought to realize that “fif” or its absence cannot prove or disprove the divine origin of any writing. An otherwise irreligious person might have a “funny internal feeling” on reading the poetry of Walt Whitman—or the lyrics of a rock song. A devout but poorly instructed Christian, relying on “fif” for his acceptance of the Bible, might sense an interior consolation when reading one of the Gospels. But what if he feels stone-cold when reading the book of Numbers? What then? If “fif” proves the inspiration of one book, the absence of “fif” would seem to disprove the inspiration of the other. If an inquirer has a “burning in the bosom” when reading the first pages of the Book of Mormon, what is he to conclude when subsequent pages strike him as relentlessly dull?
This methodology fails not just with Mormon scripture but with Christian Scripture because “fif” cannot prove any text’s inspiration. All it can do is fool a person into thinking that he has a divine assurance when in fact he does not.
Where does this leave us with the Bible? If we cannot know its inspiration from the emotional or physical sensations we have when reading it, how can we? Augustine had the answer: “I would not believe in the Gospel if the authority of the Catholic Church did not move me to do so.” We need an external authority to verify for us that this text, this collection of ancient writings, is what we suspect it to be, something composed under the direct influence of God and, so, free from all error.
We will not find that divine verification in the pages of the text itself. In few places in the Bible is there an indication that the sacred writer realized that what he was writing was inspired. You will search generally fruitlessly to find a passage that says “the following words are inspired by God.” And it will not do to fall back, sloppily, on an appeal to the table of contents. The best you will get from that is a circular argument that all but the least inquisitive minds will see through.
No, you need an independent and infallible authority that can say, “These books are inspired and belong in the Bible, and these others are not and do not.” When he walked among us, Christ himself was that authority. But he left us, and when he left he said he would send “another Paraclete” (the prior “Paraclete”being himself), and that is the Holy Spirit, who works through, protects, and guarantees the teachings of the Church that Christ established. It is the Church on which we can rely, because we can rely on the HolySpirit. When the Church tells us which books are inspired and which are not, we do not need to look for—nor should we expect—a “burning in the bosom” or “fif” because we have assurance that the Church cannot err.
If we happen to receive some sort of interior consolation when reading the sacred text, fine—but that consolation should not be mistaken for proof of the text’s inspiration.