As Calvinists we believe that God is Sovereign over all things. By saying God is sovereign over evil causes many problems in the minds of many evangelicals, and even non-evangelicals. The philosophical problem of evil is basically this: If God is all-good and hates evil, and God is all-powerful and can prevent evil from happening, why does it seem evil exists? This problem has led to several possible answers.
1. God is not all loving.
2. God is not all powerful.
3. Evil does not actually exist.
4. God does not exist.
Numbers one and two are contrary to God's revelation of Himself in His word. Choice number three says evil is not reality, we just perceive things to be evil. When one gets rid of moral absolutes, one cannot say murder is evil. This too is contrary to the ontology of God that is reflected in His law. And of course saying God does not exist is to deny both reality and the authority of scripture.
So is there a good answer to this difficult question? I pose that there is, and it is indeed biblical.
"I form light and create darkness,I make well-being and create calamity,I am the Lord, who does all these things." -Isaiah 45:7 (ESV)
"All the inhabitants of the earth are accounted as nothing,and he does according to his will among the host of heaven and among the inhabitants of the earth;and none can stay his hand or say to him, 'What have you done?'"-Daniel 4:35 (ESV)
"Is a trumpet blown in a city,and the people are not afraid? Does disaster come to a city,unless the Lord has done it?" -Amos 3:6 (ESV)
"I know that you can do all things, and that no purpose of yours can be thwarted." -Job 42:2 (ESV)
The Scriptures are clear that God is Sovereign over both good and evil. Evil does not consist of actions that thwart or go against God's intended purpose, rather, God uses evil actions to bring about his purposes. At the crucifixion, God's purpose was not thwarted when the people sinfully murdered an innocent man, rather, God's purpose was fulfilled using the evil actions of men. God most definitely could have used any means to bring about his purposes, but if God forms the light and creates darkness, if he makes well being and creates calamity, I will not argue, I will simply submit to what he has revealed in His word.