Sin isn’t about good or evil. It’s not about morality. It is entirely about obedience.
If you choose to dash babies on rocks, it’s only a “sin” because a god didn’t tell you to do it. If a god tells you to do it, it is not a sin.
Not So Polite Dinner Conversation – sin
Published
Club Schadenfreude 
I googled the meaning of sin.
Since I do not believe that any god exists, the theological meanings are (heh, heh) meaningless.
The “moral and secular” meanings seem reasonable if much broader.
“A serious shortcoming, fault, or a severe moral failing–a breach of rules.” No god needed.
I try not to use the word at all because of the likelihood of being understood as a tie to a supernatural being and the potential for secular/religious confusion.
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