Guilty as charged?

When is it the right time to feel guilt?

1. As you are committing something bad - not necessarily a sin but something out of the ordinary. could even be eating chocolate cake.
2. During the action of something bad -same as above
3. After you have committed it - same as above

What if you don't feel guilt at all? Even if you are doing something bad - not necessarily a sin but something out of the ordinary. could even be eating chocolate cake.

Could it be dismissed as confidence?

When is it the right time to feel guilt?