In order for Protestantism to work, the gravity of each sin must be flattened out to equal the gravity of every other sin. Though some Protestants hold to "degrees" of sin, for all Protestants every sin must be forgivable through the mechanism of a private act of faith.
In Protestantism, there can be no such thing as grave or mortal sin *normally* requiring the intervention of a higher ministerial / sacramental agency. Nor must forgiveness ever depend upon some consequent act of repentance, much less some restitutive token.
At best, some sort of "memory healing" might be attempted in order that psychological wholeness be restored.
Protestantism has simplified the problem of guilt to what concerns God and the individual alone and what may be managed within the individual's subjective state.
The Protestant project depends for its validity on whether guilt is simply the imputation of personal sin. But if guilt is a condition and more: the state of a community of persons--if guilt is a network of disordered relationships its remedy cannot be applied solely in the realm of private subjectivity.
And here we come to the necessity that faith be not reduced to a movement of a creaturely mind (knowledge, assent, and trust), but must be a public objective reality transcending individual minds.