As mentioned elsewhere (Question #2 in this series), human sinfulness or the fall, ushered in death (disease). The Biblical idea of human personhood is not limited to just the physical body, but also the mind and the emotions and the soul/spirit, as it were (Mark 12:30). So the effect of the fall has plunged into the deepest recesses of humans and distorted, disturbed, dampened, damaged and destroyed, the human persona at multiple levels. Psychological illness, that affects the psyche (mind), therefore is one of the ramifications of human sinfulness, in a larger sense.
In a personal sense, if one is asking, “could my personal sins pave way to Psychological illness?” Sure it can. Does it always? Can’t be so sure! There sure are ‘sinners’ (count me in), who don’t struggle with psychological ill-health. There are saints, who do struggle with psychological ill-health and challenges.
The Bible records, King David in Psalm 102:3-5 thus;
3 For my days vanish like smoke;
my bones burn like glowing embers.
4 My heart is blighted and withered like grass;
I forget to eat my food.
5 In my distress I groan aloud
and am reduced to skin and bones.
Words straight out of the note-pad of someone psychologically disturbed. This Psalm is associated with David’s sin, directly. However, most of the Psalms are not associated with sin, like this one (Psalm 102). A third of the Psalms are lament.
So, personal sins (unconfessed and unforgiven) could lead to psychological ill-health. But not all psychological disturbances stem from personal sins of the individual.
Job 16:2 is a classic case in point. Job’s ‘well-meaning’ friends look at his malady and in trying to help, they misdiagnose like most of us and prescribe pitiful pills that could escalate the malady into tragedy – but for God! The righteous Job refuses to buy their ‘Sin’ diagnosis and spills their pills and retorts;
“I have heard many things like these;
you are miserable comforters, all of you!
We should be wary of making the same ‘simplistic’ errors, like ole’ Job’s friends.