To a certain extent, self-reflection is helpful. Certainly it is helpful to realize some of the larger motivations one has in one's life. But there's a huge difference between the traditional examination of conscience and the sort of sleight of hand practiced in the psychological field. Therapists make good money convincing you that they are helping you find yourself.
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For the most part, those in a state of grace don't need to search the posterior regions of their consciousness for their motivations. Our motivations, like ourselves are here, within us. It should be obvious, even when we choose wrongly- we might ignore them, but we know our motivations, whether they be good or ill.
This is important, because it's an easy attack to take everyday pedestrian activities, and recast them as sinful due sinful motives. This can lead to very serious problems. Feeling guilty about things that are not sins is confusing and can weaken us in avoiding real sin. Also, the uncertainty and fear of not being able to rely on our decision making processes can lead to an intellectual paralysis- we may eventually not want to make any decisions at all.