2 Corinthians 5:21
ESV - 21 For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
I believe as our cultural society makes excuses for behavior that Scripture calls sin, calling most acts mistakes or wrong choices, but never understanding the concept of sin like Jesus said [Matthew 13:13].
Romans 3:23 says all have sinned and came up short. Short of what, the mark of perfection. Like shooting an arrow and it falling short of the bull's eye.
Sin as a concept is only recognized in a spiritual sense, the unborn again mind cannot perceive the reality of sin or the innate sin nature of humanity.
In a Christian sense, the sin nature is the concept and individual actions that go against God's Word are what our weak flesh continues to battle.[Romans 7:15-19]