Science relies on evidence and reason. Religion relies on faith and belief — and faith and belief have never told us anything true and valid about the nature of the world and the Universe. Therefore, science is not a religion.
We have created a justice system because, as evolution shows, we are inclined to be social and cooperative creatures, and so we codify into law that which furthers our flourishing and well-being. Miscreants live among us, and those who commit the most heinous crimes are rightly locked away. No belief in a god is needed to understand our civilizing impulses, which includes the occasional need to jail and punish certain lawbreakers.
“Satan” is a make-believe character in she same way “The Joker” is a make-believe character. You write “Basically Satan despised human beings from the beginning.” To that I will add that The Joker despises The Batman and Commissioner Gordon.