long story short, the angel lucifer (god's original right-hand man) didn't agree with the way god stated humans should be limited. he felt the concept of "sin" is rediculous and in large part counterlogical to a flesh-bound being. for example, you enjoy orgasms, but having them is a sin. the 7 deadly sins he argues are tools for empowement and counterbalance one each other, indicating that "pride" for example is a motivational force for one to make somethng of them self instead of being a derilict bum. greed is a amassing of ones own goods contrasted with being devoid. lust is the embrace of the physical sensations god bestowed upon you, and so on.

if you read the 11 laws of satanism (along the lines of the 10 commandments), you might be surprised at the actual logic contained within. whether you endorse it or not may be another story.

btw, it's a stagmatism that satanists believe in human sacrifice and blood drinking and murder and things of that nature. those things are forbidden and highly shamed upon in satanism as is the destruction of any life outside of your personal attack by a living individual.

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