NEVER, lucifer is not a human being, never was, never will be, but a different creation all together. Because of his place infront of God, there was no excuse for his rebellion, nor any provision for any grace. His was a form of the unpardonable sin.
Humanity is a separate creation from the angels. I know mormonism doesn't teach that, but you asked MY interpretation as a Christian.
NEVER, lucifer is not a human being, never was, never will be, but a different creation all together.
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scripture?