There are, I think, only two fundamental requirements that a Mormon reading of scripture must fulfill.
First, it must accept that even from their different perspectives, scriptural texts all describe the same basic reality. There is a God who exists outside of human imagination, and the scriptures have been generated through his interaction with human beings. And beyond that, the writings of each prophet and each book of scripture have resulted from interactions with the same God. Despite human frailty, cultural differences, and the limits of textual transmission and communication, all scriptural texts point to the same supernatural reality. This basic assumption justifies attempts to harmonize the gospels, or to read the Hebrew scriptures via Christian scripture as the Old Testament, or to read Paul through Alma. Perhaps all the prophets are like the proverbial blind men pawing at an elephant: but the elephant is really there, and they are all pawing at the same elephant.
I don’t think this point is particularly controversial. There are certainly other valid and useful ways to read scriptural texts that yield interesting insights: teasing out the various Isaiahs, for example, or reading the gospels as the fictionalized posthumous deification of an itinerant Palestinian preacher, if that’s your thing. You just have to understand that when doing so, you’re not likely to make statements about scripture that are relevant to Mormon devotional practice. Some people are thirsty for milk, others are hungry for meat, and you are offering them small, intricately carved statues made of granite. Statues have their uses, but they are not the first thing people reach for when they’re hungry or thirsty.
The second fundamental requirement of a Mormon reading of scripture is that it reads scripture from the inside. That is, we treat the text as being fundamentally and inseparably about us: The Creation is about the world we live in, the Fall describes the inheritance of every human being, the covenant of Abraham is still operative, prophecy continues to be spoken, the Atonement was for our sake, Nephi and Moroni saw our day, and we are on a path toward Judgment and Resurrection. We read scripture not as disinterested observers, but as participants in its internal narrative.
Again, there are many interesting statements that can be made about scripture from the outside: how the text came to take its present form, for example, or how it relates to the history and cultural practices of various Near Eastern peoples of a long-past age. I find this kind of work fascinating—but it can’t answer the “so what” question posed by an irritable Sunday School student (as Mormons, we are not dependent on an infallible or original text for our authority and doctrine). A pioneer trek re-enactment may be methodologically suspect as historical practice, but it represents an inside reading of Exodus in a way that studying a subjugated people’s fantasies of former national glory does not. The problem with the Documentary Hypothesis for Mormonism is not that it somehow threatens Mormon beliefs, but that it answers questions that Mormonism does not particularly care about. As much as I enjoy textual criticism, it’s hard to justify spending much of our limited time for communal worship and devotion on it.
These two planks of scriptural reading are not unique to Mormonism, as they largely follow how the New Testament reads the Old Testament; it is also how the authors of the gospels present Jesus reading the Torah. My aim is also not to limit what Mormons do with scripture or prescribe how Mormons must read, but to describe norms that are strongly operative among Mormons as a community of devotional readers. These two fundamentals are by themselves not sufficient for a Mormon reading of scripture, but they are necessary for anything that would be. Our understanding of scripture may still consist of blind grasping at an elephant: but the elephant is really there, and we are grasping at the elephant from the inside.