Let’s talk about cognitive modesty for a moment, and let’s talk about how Christians above all should strive to embody it. But let’s come at it with a negative example to sketch what that doesn’t look like. To this end, I’d like to use some statements Al Mohler has made as a specific case study of what Merold Westphal calls “not taking St. Paul seriously.”
Now, I don’t want to rag on Al Mohler too hard; it’s not like he’s never said or done anything good, ever. But he has a tendency to be overreaching and fractious with some of his rhetoric, and as an influential figure in the church he ought to be held to account for his novel dogmatisms and the message they send to the wider, unbelieving world. I know it’s been months already, but his response to the Ham/Nye debate was a salvo of miss-the-point pedantry that has more in common with flat earth factionalism than it does the Reformed tradition. Here’s the climax of his Mohler’s summary of that teapot tempest:
The central issue last night was really not the age of the earth or the claims of modern science. The question was not really about the ark or sediment layers or fossils. It was about the central worldview clash of our times, and of any time: the clash between the worldview of the self-declared “reasonable man” and the worldview of the sinner saved by grace.
Now, while there certainly is a worldview clash going on here, that simply isn’t the whole of it. The issue is this: Mohler is wrong to reduce this entire affair to the conflict between a biblical and an anti-biblical worldview as though the divide was that stark and that clear-cut in this instance. But I dare say this is typical of Mohler, who pairs authentic Christianity with Young Earth Creationism so consistently they seem functionally equivalent to him. Consider something he said at a Southern Baptist Theological Seminary panel discussion two years ago:
Scientists by their very nature, by the very nature of their work, are doing the best they can with the data that’s accessible to them. They’re not looking to the Scriptures for that data; they’re looking at the natural data coming from the world. But what does Scripture tell us? Scripture tells us that that world is not going to tell us the truth. I mean, Genesis 3 tells us that that world is showing all the effects of the Fall. That world is showing all the effects of the flood. That world is showing all the effects of the ravages of human sin and God’s judgment upon that sin.
There’s no question that the world shows the ravaging effects of the Fall. But to claim that “the world is not going to tell us the truth”? This is a bizarre metaphysical conclusion to reach, one entirely unwarranted by Scripture, tradition, or reason. Where does Scripture assert any such thing? Does Scripture provide any data for the age of the earth? Is that even the point of the Bible? Mohler’s pronouncement in favor of Ham leaves no doubt as to his position: the only worldview that can rightly be called Christian is one that understands the universe to have been manufactured in six, twenty-four hour days somewhere around six to seven thousand years ago. Or, in other words, that worldview which <ahem> humbles itself and understands the text of Genesis 1 as a scrupulously, empirically precise account of the mechanics of material origins. Mohler never seems to consider whether that interpretation is the best construal of the text- it just is. It stands because to not read it that way is to not take the Bible seriously. And if you don’t read it this way you can’t really know much of anything. The blind hubris of Mohler’s assertion is positively shocking.
Two things must be said:
1. It is wrong to make six, twenty-four hour days a confessional constraint for distinguishing true from false believers. This has never once been true in the long history of the Christian church ; orthodoxy has never viewed the time table for the creation of the universe as a matter of saving belief.  To assert that six, twenty-four hour days is a defining feature of what it is to be a Christian is outrageous, as is the attempt to enshrine such a flat reading of Genesis 1 as a litmus test for authentic Christianity.
2. It is wrong to sketch a dichotomy between intellectually compromised unbelievers and cognitively clean, prejudice-free sinners saved by grace. Mohler, Ham, and others of their ilk rightly draw attention to the devastating effects of sin on man’s intellect; they err, however, in suggesting that believers are exempt from those effects post-conversion (or, perhaps more insidiously, post-becoming-a-Young-Earth-Creationist, as though that was a necessary final step in the conversion experience). To do this is to not take Paul seriously. The universal effects of sin are just that: universal. They begin to be healed at conversion, but aren’t instantaneously obliterated at that moment. And while we blind ourselves in our rebellion against God, there are some things we can know prior to conversion. Becoming a Christian doesn’t magically overturn every wrong assumption you’ve ever had or give you instant, exhaustive access to everything there is to be known. The Christian tradition doesn’t provide us with a database of cosmic knowledge; instead, Lesslie Newbigin reminds us, it provides us with “a set of lenses, not something for us to look at, but for us to look through.” 
Mohler doesn’t appear to appreciate this idea because it necessarily implies some things (such as the age of the earth) can be known apart from Scripture. His intransigent insistence on knowing better because of Genesis 1 strongly suggests he is sick with the very thing he’s diagnosing- not surprising, given Paul’s description of human beings’ uncanny skill in self-deception. Merold Westphal draws attention to such culpable failures to take Paul seriously when he argues that “for believers to draw a line between themselves and unbelievers and to find the noetic effects of sin only on the other side of that line is closer to epistemological Phariseeism than it is to taking Paul seriously. For unbelief is not the only way of suppressing the truth about God. It is only the most honest.” 
Let that one sink in. The believer, sadly, is just as capable of claiming support for her personal and cultural arrogance through religion as the unbeliever is with whatever alternative route he might choose. The “substantiation” in both cases is rooted in the universal suppression of truth, and both must be unmasked by the Law and the gospel. We all smother our inborn moral reflexes with unexamined, sinful beliefs we’re comfortable with, beliefs we never think twice about until they are unmasked as sin. Even when they are, we typically dig in and defend them to the point of personal degradation. Need I give examples?
- Looking down on people buying groceries with food stamps
- Complaining about the injustice of signs being posted in English and in Spanish
- Getting too involved with ex-boyfriends on Facebook and imagining how things might have turned out
- Slapping your child in the mouth if she cries in a restaurant (because she sinned with her mouth, of course)
- Describing a collection of events in a mostly accurate way but narrating them as a series of intentional efforts you’ve made to accomplish some goal, thereby promoting yourself
- Telling someone you live in a good neighborhood when what you mean is that there aren’t any black folks living in it
- Complaining that everyone who was opposed to the war in Iraq ought to have been deported or shipped to the frontline
- Resenting that your daughter’s fiancee is Asian
- Questioning the faith of Christians who drink alcohol
- Griping that if you can’t feed your kids, then don’t breed ’em
And it goes on and on; an endless assortment of self-aggrandizing, self-justifying smear campaigns. Even if we object that we weren’t aware of those things being sin that doesn’t change the nature of the offense- it only points up our pathetic blindness and compounds our guilt. Unbelievers suppress the truth as well but don’t pretend to serve and love this God when they do so. In this respect, they’re more honest than we are when we pretend we exemplify humble and total submission to God. Such odious cracks in our lenses give the lie to the supposed moral/cognitive superiority I see being flaunted in Mohler’s response. The Christian response to grace should be a critical realism which confidently rests in what God has spoken but is willing to suspect our crooked, self-justifying motives. Christian confidence takes indwelling sin seriously and doesn’t brandish its redemption like a philosophical Death Star.
That’s a serious reality check to box the believer’s ears with, but if we take Paul seriously then we need just such a jolt to shake us out of the triumphalistic nosedive we routinely careen into, a nosedive believers are just as susceptible to as unbelievers. This is where Mohler goes so egregiously wrong: sin distorts the faculties of all of Adam’s children- the sinner saved by grace isn’t given a free pass out of this entanglement. The sinner saved by grace is still prone to deceive herself and suppress the truth when it’s convenient for her sin nature. The believer who has been purged completely of all her idols and sinful blind spots is dead. To pretend otherwise is to clothe yourself in the robes of of the epistemological Pharisee who says, “‘God, I thank you that I am not like other men, extortioners, unjust, adulterers, or even like this _________” (fill in the blank with your shibboleth of choice). To claim unclouded vision is to usurp the epistemology of the living God, a terribly ironic posture for “the sinner saved by grace” to assume. Mohler’s gambit can’t always be accusing everyone else of having epistemological specks in their eyes when the epistemological beam in his leaves a trail of black eyes and concussions he seems blissfully unaware of. Locating sinfully compromised reasoning only on the other side of the fence is itself a compromise of the Christian confession. Westphal calls it what it is: a weird detour into ideology and perfectionism.
Sin as an epistemological category cannot be, as Fichte and Plantinga, Marx and Freud seem to want it to be, merely a device for discrediting one’s opponents. To take Paul seriously is to take seriously the universality of sin. Only if perfectionism is true could even a few believing souls be noetically uncontaminated. And it would be exceedingly strange for a “Reformed” epistemology suddenly to turn perfectionist. 
Lord, in your great mercy, grant us all the grace to spurn some triumphalism; grant to us instead a willingness to suspect our sinful motives and passions; grant us the grace to repent of our pet idols and the sinful rationalizations we concoct for them; burn away everything else and impel us to promote the risen Christ and not ourselves. Amen.
 See Robert Letham’s excellent essay, “”In the Space of Six Days”: The Days of Creation From Origen to the Westminster Assembly” [Westminster Theological Journal 61 (1999)], p. 168). Letham demonstrates with extensive quotations that the church has pretty much always understood that Genesis 1 is an odd literary genre and that interpreting it well is a delicate, subtle matter.
 It has only insisted that the universe was in fact created and not something eternally existing (e.g. Aristotle’s view).
 Lesslie Newbigin, The Gospel in a Pluralist Society (Grand Rapids: Eerdmans, 1989), p. 38
 Merold Westphal, “Taking St. Paul Seriously: Sin as an Epistemological Category,” in Christian Philosophy, ed. Thomas P. Flint (University of Notre Dame Press, 1990), pp. 213-214
 ibid., p. 216