from Miroslav Volf:
For herein lies the essence of Christian forgiveness: On account of his divinity, Christ could and did shoulder the consequences of human sin; so the penalty for wrongdoing can be detached from wrongdoers. And since on account of his humanity Christ could and did die on behalf of sinners, they, in effect, died when he died; so guilt can be detached from wrongdoers. When we forgive those who have wronged us, we make our own God's miracle of forgiveness. Echoing God's unfathomable graciousness, we decouple the deed from the doer, the offense from the offender. We blot out the offense so it no longer mars the offender. That is why the non-remembrance of wrongs suffered appropriately crowns forgiveness.
The entire post can be read here.