There is an argument floating around out in the world that goes something like this: "If God is good, and God created everything, and God is omnipotent, why is there evil? God must have created evil, therefore God is not good. Or God is not omnipotent and cannot stop evil." This type of irrational thinking has led many people to deny God or deny the Christian concept of God.
"Irrational"? Why do I call that line of reasoning "irrational"? Basically, because it starts from a false premise: God created evil. Merriam-Webster defines "evil" as "the fact of suffering, misfortune, and wrongdoing" or "something that brings sorrow, distress, or calamity". In short, "evil" is merely the absence of good; evil is not a thing, and therefore not a created thing. [Another definition is "a cosmic evil force", but this falls under the line of reasoning that evil is an entity, and is therefore irrational. Strangely, Merriam-Webster violates a basic precept for this one and uses the very word inside its own definition.]
Let me explain with some examples. Is a hammer good or evil? A hammer is neither good nor evil. A hammer is a tool. I can use that hammer to drive a nail while building a house (good) or I can use it to assault somebody (evil). There are two created entities involved here: the hammer and me. The hammer merely exists, it has no will. I, however, have free will. God granted all human beings free will. I choose how to use the hammer.
OK, so God gave us free will. What does that prove? Couldn't God just eliminate evil by denying free will?
Yes, He could. But what good would that do? For most of us, the greatest possible "good" is "love". Without free will, there is no love. You will find many ways of defining love, but one thing that is important to bear in mind is that love is not an emotion. Love is a choice. Without the ability to choose, we cannot love. I am reminded of the movie, Clash of the Titans, which portrayed the Greek pantheon up on Mount Olympus moving people around as if they were chess pieces. What meaning would life have if we were mere pawns or automatons?
One more example: not all suffering is "evil". Think from the perspective of a parent. Do we not knowingly, intentionally allow our children to suffer in order that they gain a greater good? When an infant receives a vaccine shot, all the infant knows is that it hurts. The parent knows they are protecting their child from future illnesses.
Evil didn't come from God. Evil comes from those who disobey God. Everyone is guilty, "for all have sinned and fall short of the glory of God" (Romans 3:23, NASB). Satan didn't crash planes into the Twin Towers and kill 2,993 people, 19 human beings did. Some "cosmic evil force" didn't reach inside a womb and kill a baby, a misguided human physician did. Little red demons with pointy tails didn't come pour excessive amounts of alcohol down my gullet for 20 years, I did it of my own free will.