Is God Only Good in Calvinism?

I would like to propose an argument. Maybe it's been made before. I just don't know.

In Calvinism, God decrees all things, including horrible things, because He has a purpose for them to bring about good. This is the message of Genesis that ends in the statement of 50:20, "You purposed it for evil, but God purposed it for good, to bring about the salvation of many lives."

Hence, evil existing in the world has an ultimate good purpose so that God who brought about these things remains good. Like a doctor who uses the poison of chemotherapy, not to harm and murder, but to do good and save life, and so is doing good and not evil, God decrees and brings about these things to do good and save. God, therefore, is good.

This is contrary to the common statement made by freewill theists that God is evil because He decrees and wills these evils to occur.

However, I would like to turn this on its head. If God does not decree the evils of the world and bring them about for good, then these things have no good purpose. They are only the product of evil men doing evil, and therefore, they are evil acts with only evil purposes.

Yet, God, in the free will view, knows either beforehand or during their happening, that these evils will or are occurring and has either made the men and situations in which they would occur or refuses to stop them when they are occurring. What this means is that since they are opposed to God's decretive will, but not prevented by God either by His not making the men who would become evildoers beforehand or stopping them while they are committing evils, God is responsible for the evil occurring. Yet, because it has no good purpose, and is only an undesired result of making men with free will, the act is only evil with an evil purpose, as said before. This means that God is responsible for evil acts that are only evil and not good. Hence, God is the author of evil, doing evil, and therefore, evil.

It is only the Calvinist who can say that God is good, therefore, because God has decreed these things in accordance with His will to have a good purpose, and they exist in the world ultimately for that reason. Even though their secondary causes do so for evil purposes, they function as the means through which the ends which are good are brought about. Hence, like the use of poison, one can use it for death or for life, evil or good, and the purpose dictates the moral evil or goodness of the act.