“No wise man is the cause of another man becoming worse. Now God surpasses all men in wisdom. Much less, therefore, is God the cause of man becoming worse; and when He is said to be the cause of a thing, He is said to will it.”
— Saint Augustine
One of my favorite things about St. Thomas Aquinas is that he never shied away from a difficult question. Above all, Aquinas sought the truth—even if that truth led to even harder questions. One such question is: Does God will evil? Or put another way: Is God the cause of the evil we see in the world?
This is an important question, one that demands an answer because it challenges our basic understanding of who God is. If God is sovereign, all-powerful, and all-good, then how can evil exist? If He is the cause of evil, how can He be all-good? If He is not the cause of evil, how can He be all-powerful? These are the key questions we’ll attempt to answer in this post with the help of the Angelic Doctor, St. Thomas Aquinas.
How Aquinas Understands the Question
First, it’s important to understand what Aquinas means by “evil.” He sees evil not as something with a positive existence, but as a privation of good—a lack of something that ought to be there.
For example, consider a person who is blind. By nature, a human being is ordered toward sight, so blindness is a privation—a lack of a natural good. Therefore, blindness is a kind of evil. But a rock, which by nature is not meant to see, is not “evil” because it lacks vision. In this way, Aquinas distinguishes between the nature of beings and what is proper to them.
Aquinas also breaks down evil into two categories, which are essential to understanding his view:
Moral Evil – Evil that results from free choices made by creatures, especially humans, who misuse their free will.
Natural Evil – Evils such as pain, disease, natural disasters, and punishments that are not directly caused by human choices.
Is God the Cause of Evil?
Now that we’ve clarified how Aquinas understands evil, we return to the central question: Does God cause the evil that exists in the world, whether moral or natural?
Aquinas answers: No.
In response to the quote from St. Augustine that opened this post, Aquinas writes:
“Therefore it is not by God’s will that man becomes worse. Now it is clear that every evil makes a thing worse. Therefore God wills not evil things.”
Aquinas would say that both human and divine will are always directed toward the good. God does not cause evil to exist; rather, He permits evil in order to bring about a greater good as part of His divine providence.
For example, God may permit a person to sin (which is evil) because He respects that person’s free will—a good He has given them. Free will is a good, but its misuse leads to moral evil. Aquinas teaches that a person never chooses evil for its own sake, but always chooses what they perceive to be good. Because of the wounded nature of the human soul, we sometimes choose what we think is good, but which is in fact evil.
In the same way, God permits natural evils to bring about greater goods. For example, He may permit a forest fire—not because He desires the destruction—but because it is a necessary means to a greater good, such as ecological renewal or human humility. In this sense, God wills the good that comes from the event, not the evil itself.
Conclusion
God is all-good and all-powerful. His will is always directed toward the good. Because He is perfectly good, He always chooses the greatest possible good—unlike us, who, due to our wounded nature, often choose lesser or apparent goods.
Could God have created a world without evil? Yes. A world with no evil is not a logical contradiction; therefore, it falls within His omnipotence. But the real question becomes: Would such a world bring about the greatest possible good?
Just as a child receiving a painful vaccination cannot yet perceive the good it brings, we may not understand why God allows the evils in our world. But we can trust that He permits them only to bring about a greater good we cannot yet see.
In this way, it is not a contradiction for an all-good, all-powerful God to allow evil to exist.
There is so much more that could be said about the problem of evil, and I look forward to exploring it further on this page. In the meantime, if you enjoy this content, please subscribe, share, and invite others to follow along. Your support helps us grow this ministry and reach more people with the truth.