Sin induces guilt, and guilt craves therapy.
The physical problem is the guilt, but the metaphysical problem is sin.
Guilt can be induced in the absence of sin, guilt can be amplified to manipulate.
And therapy for guilt can be split off from sin - guilt can be removed by psychotherapy, which can be individual or social, and consists in denying the sin, or the reality of sin-as-such.
And therapy for guilt can be pharmacological (drugs - prescribed or not, such as alcohol).
And therapy for guilt can be to distract from guilt and displace it with another emotion (the mass media approach to therapy).
Do any of these affect the reality of sin? No - they affect the awareness of sin as a possibility and a state, they affect the awareness of sin as an emotion.
It is as if pain was abolished but not the pathological causes of pain - a person might be torn and mutilated or feverish and prostrated, but feel no pain and deny the reality of pathology.
Deny the need for a cure, reject even an effective cure if offered.
But this would be a delusion, a denial of reality - the denial of pathology being itself a pathology.
But how if the reality of reality was denied?
How if single, objective, eternal truth was regarded as a nonsense concept?
How if what someone felt (here and now) was all that was regarded as valid - and reality, pathology and sin were alike discredited as meaningless (indeed manipulative) concepts...
Once somebody was in that situation, once a society was in that situation - how could they ever get out from it - I mean escape logically, by argument?
Why would such a person, such a society, be interested by a savior, when they feel they have nothing to be saved-from except bad feelings induced by the idea that they might need saving?