Letter 74

Isidore of PelusiumUnknown|isidore pelusium
From: Isidore of Pelusium, monk
To: An inquirer
Date: ~410 AD
Context: Isidore refutes the sophistic argument that if God can do all things, he can do evil.

If someone with a taste for slander asks, "Can God do all things?" and you answer, "Yes," and then he presses, "Then can he do evil?" — he deserves to be laughed at for his ignorance, not engaged in debate. The answer is obvious: God's omnipotence means he can do everything that is consistent with his nature. Evil is not a power — it is a deficiency. Asking whether God can do evil is like asking whether the sun can produce darkness. The question is not clever; it is confused. God cannot do evil for the same reason light cannot be dark: it would mean ceasing to be what he is.

Modern English rendering for readability. See the 19th-century translation or original Latin/Greek for scholarly use.