There is therefore now no condemnation for those who are in Christ Jesus. (Romans 8:1 ESV)
Condemnation
Paul does not say there is no sin, or unrighteousness, or guilt.
The difference between guilt and condemnation is vast.
Guilt arises, in the judge’s eyes, because the guilty party did something wrong. Our feelings of guilt do not matter. We might feel guilty, but not be guilty. We might not feel guilty, but still be guilty.
But condemnation occurs when authority passes sentence on someone’s guilt. Because of guilt, authority imposes and declares serious consequences.
For Christians, while we are guilty, God condemned Christ instead of us.
Note that Paul is not saying that no condemnation took place. He is not saying that God is nicey-nice, and is no longer holy or just. Paul is saying that our condemnation already took place. So now there is no more condemnation for us.
We are peculiar, Christ was condemned instead of us.