Original Sin - Who we think we are vs. Who we really are

“Sin, especially the ‘original’ sin, goes to the core of who we think we are (free persons) and who we really are (bound persons).
When the liturgy has Lutherans in the United States and Canada saying, ‘We are in bondage to sin and cannot free ourselves,’ it has us confessing the heart of the matter.
Human nature is good – insofar as it is God’s creation.
However, because of sin it is bent, “curved in upon itself,” to use Luther’s famous saying, and worse yet, it thinks it is straight as an arrow.” 
Pg. 21 - Formula For Parish Practice: Using the Formula of Concord in Congregations
Timothy J. Wengert.