Yes James tell us that “Sins are derived from the process of atonement or forgiveness, which massively precedes them and enables them to be understood as that which can be forgiven.” I think what James is saying here is extremely profound, but Lee I don’t think he is implying that forgiveness did not exist before the sacrifice of Christ. James describes original sin as the autonomous self, that is the belief that all our thoughts and desires originate within ourselves, the belief that we are independent beings not interdependent or connected beings. This leads us inevitably to the non-recognition of the other. What he was saying previously about how we should not linger over, or agonise about our own peccadillos, means that we should learn to forgive ourselves, which enables us to forgive another as we come to realise that we are all wounded, broken people. This is the beginning of compassion and interconnectedness. And this is how, in forgiving, we come to realise the true nature of sin. Does this help?
