For example, a complete surrender to ↓ will get the job done, although the same cannot be said of a complete commitment to ↑, since man cannot pull himself up by his own buddhastraps. I mean, he's welcome to try, but just where does he think he's really going? He's going nowhere, but he only discovers that when he gets there. Then he and the roshi presumably have a big belly laugh at the folly of man's delusions.
According to Pieper, the "↑ is all you need" approach -- i.e., the sufficiency of the human will -- falls under the rubric of "pelagianism," which is "characterized by the more or less explicit thesis that man is able by his own human nature to win eternal life and the forgiveness of sins."
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The converse form of presumption -- and you Protestants will want to discuss this quietly amongst yourselves -- is the idea of "the sole efficacy of God's redemptive and engracing action" and "the absolute certainty of salvation solely by virtue of the merits of Christ." (And please never forget that I'm hardly an authority in these matters, just a guy blogging it up as he goes along. If slide effects occur, consult your local holy man.)
It reminds me of what Dennis Prager often says about so-called liberals who personally lead very conservative lives, and yet, don't have a political philosophy in accordance with that fact. There is a weird disconnect between how they conduct their own lives and what they believe. The people who actually do live out leftist ideas are more or less the dregs of society. They are not following a recipe for personal success, to put it mildly, unless they are already wealthy, or pursuing a line of work in which depravity is a prerequisite, such as politics or the arts.
Just so, I find that most people who believe in the sole efficacy of salvation through Christ rarely behave that way. Rather, they are generally very much interested in ↑ to go along with the ↓, i.e., aspiration + grace.
Again, if they're not, then they tend to be insufferably smug and difficult to be around. Frankly, these are the types of people who give others the Jesus Willies, and rightfully so.
For if one has already achieved salvation -- neener neener neener! -- not only is there no need to aspire, but there is a kind of implicit invitation to moral license, since it's all forgiven in the end. It turns God into a kind co-depenent wife of an alocohlic. Every time she "forgives" her husband, that releases his guilt and sets the stage for the next transgression.
I have definitely noticed this pattern in certain patients from the south, and now that I think about it, you can also see it in that first generation of rock & roll pioneers, who were all from the south and had similar religious roots -- Elvis, Jerry Lee Lewis, Little Richard, Johnny Cash. Each of them at times led lives of utter dissolution, but it tended to be a saw-toothed pattern of indulgence and repent, with no true forward movement. Rather, the repent just creates a clean slate for the next fall.
I remember a story about Johnny Cash, who had invited a couple of members of U2 for dinner. At the table they held hands in a circle while Johnny said a solemn grace. At the end, he pauses and says, "sure do miss the drugs, though, Lord." The film that came out a few years ago is rather misleading, since it implies that his drugging days were over by 1967, but that is not the case.
This type of person may even be happy to concede that he is "the biggest sinner of them all," but mainly as a way to unconsciously explain away the future sins to come. Ironically, it is a form of pride, as if to say, "my sins are bigger than yours, so look how much God has forgiven!" You might say it is a humble lack of humility.
Augustine said that "only to the humble is it given to hope" (in Pieper), so that the presumptuous person cannot even genuinely pray "because he fully anticipates its fulfillment."
Pieper makes the more subtle point that in tipping over into either despair or presumption, one eliminates the dialectical tension, as it were, between divine justice and divine mercy.
But in reality, in hope there should be no separation between divine justice and mercy; rather, we only create it by falling to one side or the other. From our standpoint, justice and mercy may appear to be at odds, but in God they "are actually identical."
One has only to think of one's child to understand this. Discipline is not an end in itself but a kind of mercy, precisely. The child may protest that you lack mercy in not allowing him to eat M&M's and Doritos for breakfast, but the opposite is true. It's nice to have all your teeth.
Remember that wise crack to the effect that wisdom begins with the fear of God. It is this fear that presumption eliminates. Pieper points out that Saint Thomas "lists not only disordered fear but also unnatural fearlessness" as Neddy no-noes to be avoided. Fearlessness is a form of immaturity and self-deception. Again, I have a child who happens to be rather fearless, so in his case, he needs to cultivate some rational fear in order to grow in wisdom.