Most of the time when people talk about what the cross achieved, they do so with the perspective that Christ came to eradicate bad behavior, culturally (whether socially or ecclesiastically ) deemed as immoral. However, the scriptures, while not being silent about sins, insists that mankind’s problem is sin. That is, they have a problem at their core. Sins might be manageable. Either with moral therapy or behavior modification, one might be able to subjugate habits and activities over a period of time or for scheduled periods of time (like Sunday ). This kind of moralism does not touch the notion of sinfulness that is so integral to the fabric of human nature that it renders the will, mind, and heart bankrupt of desire or ability to battle it (Romans 1:18-23; 3:10-18, 23).
The cross is there not to save us from sins, which can be managed to various degrees, but to save us from sin, which, due to our natural and contented slavery to it, we are bankrupt of will or resources to remedy (Romans 3:23-27; Titus 2:11-14).