The sin is the lie, or intent to mislead - unaffected by the justification that it was just about a small matter...
The sin is the spite: the wanting to harm another for one's own gratification - not in the magnitude of that which is wished upon them.
The sin is in the resentment - it does not matter whether criticism is 'deserved'.
Evil is in the believed and argued inversion of virtue - not in whatever harmful consequences of this inversion.
