“Is God willing to prevent evil, but not able? Then he is not omnipotent.
Is he able, but not willing? Then he is malevolent.
Is he both able, and willing? Then whence cometh evil?
Is he neither able nor willing? Then why call him a God.”~Epiricus
The above is something I have heard time and again as a refutation of an all powerful god. Now I don’t know about you, but I happen to believe that God exists, specifically the new testament christian god, but that is really irrelevant to the argument. When the above quote, or even just its concept, is used as an argument or explanation for why someone does not believe in God (or higher power or whatever) it show ignorance and a lack of critical thinking ability.
Apologies if that sounds overly harsh and offensive, I really do not mean harm, and I definitely believe you are entitled to your own opinion, religious or otherwise, but I try to stamp out logical fallacies wherever I see them, and whatever the subject. The above especially so since I have had friends use it in religious debates, expecting that it was the winning blow and end of the argument. It is not.
That being said, I will lay out why that is a logical fallacy and also seek to explain a possible answer to the implied question (that is: if there is a god, and he is good and all powerful, why is there evil?)