Hi there Northern Star, you wrote:
"...but that if the murderer himself would not talk to the police, they would not pursue the matter further... Cognitive dissonanceā came to mind..."
Did they give any sort of rationale for their conclusions because they're not just experiencing cognitive dissonance, they're experiencing cognitive disintegration.
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Here's a simple question for them: Do they pay taxes?
If they answer in the affirmative ask them why do they pay taxes? What is the scriptural basis?
Now every government on this planet today requires that citizens HAVE to report a matter if they have witnessed a crime or are aware of an unreported crime. It is a part of each citizens civic duty. IT IS MANDATORY, just like taxes.
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The rule for any sane human being regardless of faith should be the following: Its not just a sin its a felony.