Daniel Kirk offers an excellent post on how the various ways we can speak of atonement relate to the various ways we can speak of sin. I particularly like Dan’s conclusion:
once we’ve so expanded our vision of what living in a sinful world entails, we are confronted simultaneously with the various ways that we need all of Christ in every area of our lives.
If we have anger problems, that not only means we have guilt in our anger that needs to be forgiven, but likely some brokenness in our way of responding to the world and woundedness in our hearts that need to be healed before we can respond to our world with grace and patience. Moreover, if we have such a problem there is a power working to enslave us to this sinful passion from which we need to be freed.
And so I make the modest suggestion that when we deal with sex as a particular issue, we must anticipate that we will see evidence of sinful expressions that need to be forgiven, seemingly inescapable desires from which we need to be freed, and driving forces in broken and wounded hearts and bodies that need to be healed.
To claim that God is not concerned with what we do sexually is to revert to an insufficiently physical gnosticism. To cordon off sex from the realm of our humanity possibly marred by sin is to insufficiently recognize both the need for and extent of Christ’s atoning work.