I mean this post to complement Tracy M’s reflections on the same talk. Go read them if you haven’t already.
I hope that President Uchtdorf’s Sunday Morning sermon becomes a landmark, because of the smart way that it approaches the fraught theological territory surrounding works and grace. The point here isn’t the theological smarts, but the potential for pastoral comfort. We talk sometimes as though the intellectual and the spiritual can’t coexist, but I think that they inevitably do. And, as someone who believes that being critical about our God-talk matters, I’m persuaded that bringing our minds fully to bear on spiritual matters can be of great pastoral benefit, which is why I am praising this sermon.
Traditionally, the works/grace issue is a problem because each side has an easy reductio ad absurdum with which to hammer the other. From the grace side, it’s Pelagianism, or the idea that humans are technically capable of saving themselves by perfect obedience, thereby obviating the need for a savior; from the works side, it’s antinomianism, or the idea that, since God really does all of the work in salvation, sin as a category ceases to matter, and so you have people doing things like reading “to the pure all things are pure” and believing that they can have sex with other people’s spouses without committing adultery—all hell, in other words, breaks rather ironically loose.
The modern incarnation of this debate goes back to Luther and Erasmus in the 1520s. (I believe in complete sincerity that every person needs to read their debate, because it structures so much of Western culture.) My quick and dirty take is that the whole thing hinges on math. Both Luther and Erasmus believe that the overall human contribution to salvation is basically infinitesimal, but, because math wouldn’t really know how to grapple with infinitesimals until the 19th century, they disagree about whether these tiny quantities are something (Erasmus) or nothing (Luther).  In terms of historical influence, Luther won the debate, in part because his solution is nice and clean, whereas Erasmians have to traffic in all kinds of nuance about “not nothing” and the like. 
What I’m suggesting here is that math offers a way out of the impasse, by enabling us to embrace human obedience as an infinitesimal quantity, which, I submit, is precisely what Uchtdorf does. He begins by emphasizing grace, when he asks what a sheep (in the parable of the lost sheep) needs to do to be found:
Does the sheep need to know how to use a complicated sextant to calculate its coordinates? Does it need to be able to use a GPS to define its position? Does it have the expertise to create an “App” that will call for help? Does the sheep need endorsements by a sponsor before the Good Shepherd will come to the rescue?
No. Certainly not! The sheep is worthy of divine rescue simply because it is loved by the Good Shepherd.
If he’d stopped there, he’d be open to charges of antinomianism: God loves us no matter what, so he’ll save us no matter how mired in sin we happen to be, so laissez les bon temps rouler and so forth.
But he doesn’t stop there; he goes on to redefine obedience in what I take to be a fairly radical way for a Mormon: insisting that “God will not rescue us against our will,” he frames obedience as a simple act of turning to God, following the scriptural invitation “Come unto me.” This act marks the first step on a path of faith, but once we’re on the path the abundant grace of a loving God accompanies us.
The important detail here is the small simplicity of the act, which Uchtdorf anticipates will prompt some incredulity in his listeners: “But, you might be thinking, what is the catch? Surely I have to do more than simply wait to be rescued.” Although Uchtdorf does close the door on Lutheran passive obedience, his form of active obedience is structurally designed to resist the charge of Pelagianism, in that he makes it progressively smaller:
If you cannot say you know God is there, you can hope that He is. You can desire to believe. That is enough to start.
Far from the impossible demand of Pelagianism, Uchtdorf works to bring the necessary act ever more within reach—right up to the boundary between something and nothing, such that the most microscopic shred of hope or desire, followed by the slightest gesture of prayer, becomes enough.  This boundary provides the opposition necessary to the plan, because it’s precisely the guarantor of meaningful agency.
As a “mere catholic Christian,” I’m highly sympathetic to this solution (and not just because it’s also Richard Baxter‘s solution). It gets quite deftly down to the absolute fundamentals of faith in their most basic form. This approach provides a point of unity for people who may differ about the rules and procedures that inevitably get built up on this foundation, as a practical consequence of community needs for order and other concerns. More importantly, it opens the door of belonging to more people, which is a big deal, given the door we’re ultimately talking about.
Being aware of the ramifications of the terms in which we carry out our God-talk matters, especially given the way that theological decisions end up drawing boundaries of inclusion and exclusion. Such awareness need not take the highly esoteric form of this post; in fact I’m grateful that Uchtdorf could do the necessary work in his sermon without resorting to such nerdery. It’s the awareness that counts, not the technical language. So, I salute him for a sermon that I hope will keep us all thinking and feeling for a long time to come.
 Liebniz and Newton, when they developed integral calculus in the late 17th century, fudged this issue too, treating infinitesimals as zero for purposes of subtraction and non-zero for purposes of division.
 Luther won in the sense that we got the Protestant Reformation as our conceptual category for understanding what happened, even though a straight Lutheran view on grace is probably now a minority position. That Luther won still really irks Erasmians, 500 years later. (Trust me on this: I was hanging out with members of the Erasmus of Rotterdam Society just the other night. [Yes, really.] They’re cool folks, though more than usually likely to drop Latin in casual conversation and just expect that everybody knows what they’re talking about.)
 Sure, this move is still vulnerable to the anti-Pelagian reductio. I have a massive pile of polemical works, both published and unpublished, from the 1650s to back me up if you don’t believe me. Still, I think that the mathematical sophistication wins, because people in the 17th century weren’t quite in the position to think about the tiny irrational number that by definition exists between the smallest possible fraction (1/∞) and zero, because the reductio depends on a binary ontology that such a number by definition refuses. [∞ is really aleph-zero, the countable infinity of natural numbers, but I couldn’t get that to display in WordPress.]