Welch’s basic map is actually very useful. The question is one of subjectivity and agency. Modern psychology is generally, though not entirely, under the spell of the “hard” sciences, which means, mechanistic figuration. This means that much of modern psychology will tend toward an impersonalist, materialist account of human behavior- not just abnormal behavior, but normal behavior too. As Welch notes, there are in fact basic physical injuries or imbalances which lead to behavioral abnormality, and for which the person is not culpable. And there are in fact conscious decisions which, however sneakily or self-deceivingly executed, are the person’s full responsibility. But then there is a vast range of things which are neither one nor the other exactly, and many of these are impressions and habits of soul which predate age of reason or full moral agency, that is, date from childhood exposure to traumatic circumstances when the person is still very plastic and impressionable, and deforming responses developed to such trauma can be very compelling and experienced almost as “nature”, rather than habit. Too, even in adulthood, certain kinds of trauma can strike a person’s heart so profoundly that pre-conscious deformative responses are developed in reaction. And these deformations can create certain specific dispositions to sin, though, as Welch notes, barring real insanity, we have to assert that the person is not compellingly determined to sin by these complexes.
The problem with Freud, of course, is that although he described “neuroses” with great acuity, he regarded the human person as epiphenomenal to a mechanical (he liked hydarulic metaphors) libido which was “channeled” this way or that by stimuli, rather than seeing neuroses as responses of the whole person, though at levels which seem or feel pre-conscious or unconscious. But the truth is that “neurotic” responses are in fact responses of the whole person, though we cannot identify the whole person with the fully “conscious” ego which we habitually regard, in reflection, as the “self”.
Thus far, any philosophical psychology can and should go, and in this regard, I recommend highly the works of JH Vandenberg and the other phenomenological psychologists of the 20th century.
What then is the specifically Christian difference? There must be one, by Brunner’s Law, because this isn’t math or physics or carpentry. This has to do with the image of God and his God-ordained path to blessedness. The problem with many “Christian” approaches is that, as the Dooyeweerdians rightly note, they work with a picture of a “spiritual” man who is basically an angel in flesh, but ahistoric and simple. Thus, there is a tendency to want to reduce all psychotherapy to either a) exorcism, or b) church discipline. This is an enormously stupid mistake. In reaction, we now have Christian counseling which, although it might be fine philosophically (meaning, personalist and non-materialist), is hardly Christian at all, though in a secularist and materialist age, philosophical rectitude is already *so* different from the prevalent model that Christians can mistake it for being specifically Christian. So what is the Christian difference?
I’d say that in part it lies in pointing out the sinful nature of deformative responses even if they aren’t per se sin or conscious sin. The old distinction between original and actual sin is useful here. If I’m bullied badly as a kid, and no adult steps in to restore justice, I might develop some really ugly wrath-responses which, although quite intelligible as self-defense maneuvers, derive from my fallen heart’s supposition of scarce, merely general, or even nonexistent Providence (not knowing truly that God is my Father), and ignorance of unity of man and the divine law of charity. And most specifically, the fallen heart is ignorant of the fact that God’s Son has absorbed and quenched in His flesh all sin, not just of man against God, but of man against man. Or I might develop fear-introversion responses; but the roots would be the same- original sin, by which I am totally depraved. Merely philosophical psychology runs aground here precisely on questions of constitutional depravity, and also of theodicy, and here, it has to be informed by Christian revelation in order to be of final use to people.
We cannot bypass the specific personal history and habituation of persons and reduce their problems, if they are genuine, to abstract “sin” categories, though those categories are certainly relevant to the consideration. The complexity and depth of original sin is, as it were, transpersonal; and grasping the historicity of persons is essential in getting to the cure of them. But must also insist that life in Christ, although not a magical abolition of problematic history, is indeed redemptive of it, and not just in the abstract. The concrete ways it is so can be shown in particular cases.
With some qualifications, I recommend the the works of Tournier as exemplary.