Question: Did God create evil?
Answer: Some people say that the existence of evil disproves the goodness of God. The argument is that if God created everything in the world and evil is in the world, then God must have created evil, and if God created evil how can He be good?
The flaw here is the assumption that evil was created in the first place. Is there such a thing as light? Yes, of course. Is there such a thing as darkness, the opposite of light? No. Darkness is not the opposite of light, rather it is the absence of light, and an absence can't be created. If darkness was a "thing" then we could make dark, which we can't. All we can do is take away light.
How does this relate to God and the existence of evil? If darkness isn't the opposite of light, but the absence of light, then is it possible that evil isn't the opposite of good, but rather the absence of good? If evil is the absence of good, then it couldn't be a created thing, and if it isn't a created thing, then God could not have created it. Evil is not the opposite of good, but the absence of good.
What about Isaiah 45:7 which says, "I form the light, and create darkness: I make peace, and create evil: I the LORD do all these things." (KJV)
God isn't the author of moral evil, but rather evil in contrast to the peace of the previous clause. In this passage, God is correcting the eastern philosophy of two eternal supreme beings (Good and Evil) constantly at war with each other. Here is a quote from Adam Clarke's Commentary on this subject:
[I form the light, and create darkness] It was the great principle of the Magian religion, which prevailed in Persia in the time of Cyrus, and in which probably he was educated, that there are two supreme, co-eternal, and independent causes always acting in opposition one to the other; one the author of all good, the other of all evil. The good being they called LIGHT; the evil being, DARKNESS. That when LIGHT had the ascendant, then good and happiness prevailed among men; when DARKNESS had the superiority, then evil and misery abounded. An opinion that contradicts the clearest evidence of our reason, which plainly leads us to the acknowledgment of one only Supreme Being, infinitely good as well as powerful. With reference to this absurd opinion, held by the person to whom this prophecy is addressed, God, by his prophet, in the most significant terms, asserts his omnipotence and absolute supremacy.
The word translated "evil" by the KJV is the Hebrew "ra.'" It can also be translated "calamity" and is translated as such in the New American Standard, New American Standard Updated, and the New King James version. Other translations render it as "woe" (Revised Standard Version), or "disaster" (New International). As for creating darkness, in Ezekiel 32:8 God says exactly how He creates darkness: "All the shining lights in the heavens I will darken over you and will set darkness on your land," declares the Lord GOD.(Ezek 32:8)
How does God create darkness? By taking away light.