In ancient times religionists were puzzled about how a good God could permit evil to be. They came up with a simple solution or at least they thought it was a solution. They said there was an all-good God but whose power to do good was limited by another God, a bad one. By bad, a God who likes to make people sin, or torture them or be vengeful to them or all three is meant. These two Gods have to be equal for one could bind the other and take over everything if one was stronger. They have to compromise all the time and neither can act without the consent of the other. This doctrine is known as Cosmological Dualism. Today, it is hidden in Christianity. While it is heresy to argue that God and Satan are equal, many believers act as if they think they are. And all the while paying lip-service to God Almighty. Jesus in the Gospel of John grants immense power to Satan and tellingly never attempts to cast demons out. He was one example.
To many today it appears that suffering can be explained by the notion that Dualism is true. We are told, "The theory implies that we live after death for some people have lots of happiness/misery on earth while others who should have it more do not." This assumes that the gods claim each person equally. That is not necessarily true. It is not necessary if the goal is to have a universe where it is all half evil and half good. The deal might be for Joseph to have a good life at the expense of Jane who is swallowed up in suffering.
The Gods could have decided that rather than moral good and moral evil, everything should be both good and evil. It would mean that to help one is to harm another. That is not how life works. While we may engage in actions that are both, most times we do not. I think a moral neutral setup across the board would be more likely if there were really two incompatible Gods.
Would good God accept some souls to care for non-stop forever and let bad God have the rest to torment non-stop forever? Maybe for the result is as much good as evil. Perhaps instead of each taking his share in this way that each will let the other treat all of them as he pleases at times. Accordingly all of us will have pleasure and then sorrow and then pleasure and sorrow again and so on for all eternity. It certainly looks as if that is what they are doing. Yet it makes no sense for people to flip back and forth. Bad God would be more interested in spoiling virtue and defiling good things for he hates the Good God than in cruelty. Good God would be more interested in the redemption of the wicked from evil than in having people who have never strayed from him. Both Gods are just playing games. For example, how could a loving God want to reform you when the bad one gets you by evening?
Bad God would be doing the happy people a favour if he let Good God have them so that they will never ever suffer. That would actually be okay if he could not have his own way all the time. It would not mean he was good of his own accord.
The Gods are not infinite. You cannot have infinite good power and infinite evil power for infinite power means having all possible power. Infinite power cannot be all evil and all good. Bad infinite and good infinite cancels. Why then honour good God for he is really no better than an angel or something? You may as well worship the president. You can only trust that his intentions are good but what use is that when you need help?
Dualism does not necessarily imply reincarnation. The soul could be a kind of body that is not sensed until death and which enables life, and pain and happiness to continue.
In the early Church, some heretics believed that the body and the world and all that is material is evil and the handiwork of an evil God. The Good God is the maker of spiritual things, spirit is what has no parts and is so potentially indestructible. They believed that matter was evil for it stank of decay and death and forced the mind to forget about the things of the good God. Matter need not be evil but it is evil the way it is. But if we are made for God alone if he exists as Augustine and Jesus and reason say, then we don’t need bodies and having them would tell us that God does stupid things for a soul would do.
Many of the heretics argued that a person who was attached to material things would be reincarnated and come back to this world after they die. And that was seen as a bad thing. The goal was to escape matter and the body. Until a person becomes totally in line with the good God and contemplates and wills to be with him alone they will be reincarnated. That means that the person must have no dependence on matter at all. For some this meant starving to death. For others it meant a body eating and drinking and taking care of itself while the soul or mind was preoccupied with God and not even knowing what it was doing.
The evil God is made out to be an outrageous villain who knows only how to be vicious. This God appears insane rather than evil! We should not have to invent a God and then slander it as evil in order to explain human suffering and how unjust it is.
Evil is evil. It is about the anti-principle. The evil God may be portrayed as a tormentor but he does not have to be. All evil people oppose evil and the reason they are evil is that they have their preferred evils. Their opposition to evil is hypocritical and prideful and confusingly is itself evil. Evil God could be evil if he wanted to turn us into aimless hedonists rather than torment us. Cartoon villain evil is only one form. We fear that form of we are more interested in being healthy and happy than being truly good.
The fastest way to prove that the theory is untrue is that there is no free will and that none of the arguments for a good God work. If we had no free will and these Gods existed, life would be different for we would be obviously puppets. Also it robs moral effort of any purpose.