Sin is an invention of priests who need to have a lever to control us, to get us feeling guilty and fearful, and to get us feeling forgiven with their rituals.  That a god's death could provide forgiveness for sins is illogical and in fact rather dumb.

Suffering is the evil of the world, not people's bad behavior, and to the extent what we do causes suffering there is no cosmic forgiveness and only what forgiveness we can give ourselves or others give us.  One should undo the harm as much as possible and learn what lessons one can and then get on with life -- accepting whatever consequences may follow form what we do.