Sorry for the long text, but you’re asking a complex question that’s difficult to settle, so it can’t be answered with a simple slogan. (Disclaimer: I wasn't able to write this in English directly, I wrote it in French and automatically translated it into English)

At last, a good question. My remark about rounded squares wasn’t entirely off topic. I simply wanted to point out that it was important to understand why the philosophical definition of omnipotence posed fewer problems than its general definition. And that didn’t come out of nowhere: by the time the paradox in question was devised (it doesn’t date back to Epicurus, but it did arise much later), debates about how to define omnipotence were already underway. To understand what this paradox means, we also have to take account of the debates of its time.

If we don’t reject God simply because he is unable to do what is impossible, then we have to examine the state of the world and the presence of evil by asking whether a world without evil could have existed. If the answer is yes, then we can indeed say that God is evil. If the answer is no, the question shifts: the problem—or mystery—of evil becomes this: would it have been better to exist with evil and suffering, or not to exist at all?

Let’s begin with the first point: could God have created a world without suffering or evil? We must first define who God is. Of course, this definition is confessional; it is not universal. I base it on my own religion. Other religions will probably have different answers, just as legitimate, but I cannot speak on their behalf.

Let’s return to the so-called Epicurean paradox, since that is where this discussion begins. Imagine a God who is omniscient, good, and able to do everything that is possible. Could he have created a world different from ours?

If we stick to the fundamental principles, there are three possibilities. The first would have been to create nothing. But would a good God want to remain alone for all eternity? Is it good for there never to be a universe, existence, life, sun, stars, happiness, or laughter? A good God can only be a creator God, because he wants happiness to spread.

The second possibility would have been to create a world entirely subject to his will. God is good and knows what is good, so all he would have to do is decide, and his creation would obey him perfectly. But the world he created in this way would not be independent of God. It would be no more than a play, a puppet, something that looked alive without really being alive. So a good God cannot create such a world: he must create a world independent of him—and, precisely because he is good, a world capable of evil.

Here we need to take a detour to define evil. In my view (and I recognize that this is a personal definition, among others that are possible), evil is not a reality in itself, in the same way that good is. It is the absence of good. Imagine God as the Good, with a capital G, like a radiant sun: the farther one moves away from God, the farther one moves from the good, and the more evil there is. The only way for there to be nothing but good would therefore be for there to be nothing but God. Consequently, a good God could not create a world that was nothing but good. That leaves a third possibility: to create our world, a world created for good and by the good, but different from God and therefore different from the good. A world in which evil is possible.

But if God is all-powerful, can he create a world governed by different logical laws? What would prevent him from creating a world entirely different from him and yet perfectly good? In other words, do the laws of logic apply to God? And if so, where do they come from? My answer is that the laws of logic do not apply to God from outside; they are in God and are part of him. The only limit to divine omnipotence is omnipotence itself. God cannot do anything other than love, or be anything other than logical, because that is part of his very being.

In short, a good, omniscient God, able to do everything that is possible, would have had no choice but to create a world like ours. The question that remains is whether that is better than not existing at all. This question remains open and complex; we cannot fully resolve it. The absence of a universe is impossible to imagine, so we have no way to think, analyze, or compare in order to reach a conclusion.

By contrast, the dichotomy you draw between a God capable of anything, including creating a perfectly good world completely different from himself, and a God who abandons the world to evil is false. The Bible tackles this question head-on. A good God who created a world in which evil exists cannot leave it as it is. He acts in the world, but not in a way that would crush it and turn it back into the kind of play we saw he could not create, because such a world would be worse than the one we have today.

Evil does not concern humanity alone. As I said, evil is the absence of God. The world is, by definition, other than God. Evil therefore does not concern only beings with free will: natural disasters, death—including the illnesses of young children you mentioned earlier—are also consequences of the fact that the cosmos is not God. In other words, evil is not only a moral question; I would even say it is not primarily a moral question, since our moral judgments and reactions are themselves shaped by biological, social, psychological, and other factors.

That is also why the Bible is not a manual that can be understood immediately, but rather a place where God and human beings encounter one another through reading, meditation, and prayer. God is so different, so powerful, so much greater than our human words and minds that we cannot measure up to his greatness. We cannot understand the divine will. That is not a limitation of God, but of us.

To avoid crushing the world with his omnipotence, God holds back while also entering the world: he himself becomes part of it. That is the whole meaning of the incarnation of Jesus Christ. The incarnation is God choosing to become human in order to share in human life, death, and resurrection.

It is in the promise of resurrection that we find one of the two ways God acts in the world. He does not merely watch what happens; he prepares what comes after. That future is a reconciled cosmos, one that has known evil and can now choose the good—not because it is compelled to, but because it knows it, understands it, and has experienced it. Its choice is therefore free and fully informed, without divine intervention that, by the very force of divine omnipotence, would once again turn the world into a play.

The other way God acts in the world is mysterious, but powerful: he awakens in us the desire for good and the desire to love. He guides those who are willing to be guided, while fully preserving their freedom, never becoming a controller.

God’s omnipotence is therefore not expressed through absolute control that denies the other, but through an infinite capacity to accompany. The paradox is not resolved through force, but through love: a love great enough to accept the risk of evil, humble enough to become incarnate in suffering, and powerful enough to transform the world through the reconciliation to come.