So does that mean you worship Satan or something?
It would be hard to worship anyone who I don't believe in, and strangely I believe in neither your God nor your devil, generally speaking for the same reasons.
I know that I can say 'your god' and 'your devil' from the question that you ask. The very fact that people sometimes ask it reveals something about those people. It shows their focus on the a specific way of thinking, the very polarised one dimensional view that God is at the good end of the spectrum and Satan at the other. Outside that single dimension, as most atheists realise, there are other gods that we equally disbelieve in. (Muslims fall into the same trap of course.)
Satan is unique to the Abrahamic religions. In particular Christianity and Islam focus on his evil role. One would not expect a Buddhist or Hindu to believe in Satan because their systems of belief simply do not include him.
Similarly I think it is unlikely that any Atheists believe in Satan, let alone worship him or work for him.
Some people who have irrational thoughts about invisible sky beings have to believe in invisible underworld beings, and they chose all sorts of pejorative methods to undermine people who do not share their views. This type of argument is known as 'the straw man'. It is rarely a technique that improves understanding of an argument.
Those of us who do not believe in ridiculous, inconsistent and unsupported ideas, written down by peasants in the bronze age, in one of the most illiterate parts of the world, have no such need. How does the idea of Satan help to explain anything about the world when the god that you worship is so manifestly evil anyway?
You might have noticed that the term 'act of god' always means something bad. Whether it be earthquakes, storms or pestilence, if you believe in a god then you have to believe that he is a uncaring and ruthless monster.
How is there any room for Satan, who presumably is even worse than God? Maybe you believe that he uses techniques of sweetness and light to lure people to an unpleasant eternity. Atheists don't.
Or perhaps you confuse the word 'atheist' with the word 'satanist'? It would be an easy mistake to make. They both end with 'ist'.
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