Some thoughts of C.S. Lewis on the issue of omnipotence of God:
His Omnipotence means power to do all that is intrinsically possible, not to do the intrinsically impossible. You may attribute miracles to Him, but not nonsense. This is no limit to His power. If you choose to say 'God can give a creature free will and at the same time withhold free will from it,' you have not succeeded in saying anything about God: meaningless combinations of words do not suddenly acquire meaning simply because we prefix to them the two other words 'God can.'... It is no more possible for God than for the weakest of His creatures to carry out both of two mutually exclusive alternatives; not because His power meets an obstacle, but because nonsense remains nonsense even when we talk it about God.
– Lewis, "The Problem of Pain" 18
My thoughts on this subject:
This is the same as the old "Can God make a rock so heavy that He cannot lift it?" It's kind of nonsensical, and really dosen't address the Biblical Omnipotence of God anyway.
Biblical omnipotence is translated in many verses as God being Almighty and that with Him all things are possible. Not nonsense things like making rocks to big for Him to lift, but that He is capable of enacting His will here on earth. Since God did give us Free Will, not all of His perfect will will come about. But, He is more than capable to enact what He does will.
A good example though of the omnipotence of God can be found in stories like the birth of Issac. Abram and Sarai were too old to have children, but it was God's will that they would have a child of promise. They almost blew it with the whole mess with Hagar, but after they messed things up with their venture into free will, they turned back to God. When they did they found that it was indeed possible for an old man and an old woman to have a baby.
Sometimes when thinking through ominpotence, it's good to consider the fact that Jesus told us, if we have faith the size of a mustard seed, we could move mountains. Well, there have been Christians of considerable faith throughout the ages, so why haven't there been any mountains uprooted? Because faith by definition is characterized by submitting one's will to God's. And, it really isn't to any of God's purposes to be tossing mountains around like so many matchsticks. Perhaps God can pick up Everest and turn it upside down. Actually, given that I have faith, I could do it myself. But, don't worry, I'm not in the least bit interested in flipping Everest because God isn't giving any particular instructions in the matter, so there is no reason for me to be doing it. Without the reason to do it, there is no faith required for such an act. Perhaps someday in the future, when this earth is finished, why we might find that by flipping Everest, the new earth will be revealed. If that winds up being the case, and God informs me that I'm the designated flipper, I'll have no doubt that I'll have no problem in doing so.
Regarding Epicurus, I see a basic flaw in the 'paradox'. That is that God is wicked if He doesn't abolish evil. God IS abolishing evil. He just isn't doing it to Epicurus' liking. Epicurus would abolish evil in some kind of immediate way. God isn't working like that, He is going about it differently. Epicurus thought that pleasure was good, pain was bad. God doesn't view things this way. Sometimes pleasure can be very bad and pain can produce wonderful things. While Epicurus would have that all pain is wicked and God would be wicked if He doesn't abolish pain right away, God is more interested in working through the evil and pain of this world rather than simply lifting us out of it.
Because Epicurus was centered on pleasure, and making the conclusions that he made regarding evil, in his mind the gods didn't interact with humans. Frankly, I think he was most likely an atheist, but I'll admit to not knowing all that much about him. Sadly though, in the end, he didn't escape pain, was wracked with kidney failure and dysentery and found happiness only in that he was about to die and cease existing altogether. (1)
To the Christian, God has a much more optimistic plan regarding evil. Yes, in this world we will face the consequenses of evil and experience pain. But, He Himself took on evil, vanquished it and when the fullness of time comes, will banish it. At that time we will then be able to have unending pleasure, the kind of pleasure that Epicurus sought but failed to attain.
Also, the Christian has another encouragment. Even as our Lord told us, "In this world you will have tribulation" He voluntarily subjected Himself to that same pain and humiliation that we suffer. In Epicurus' world, the gods were both indifferent and ineffectual to relieve him of his final pain and death. In the world of the Christian, we have a God who is sympathetic to our sufferings as He suffered Himself, but He also did what was necessary to finally defeat death and is now waiting for the fullness of time to bring the end of all suffering.
If you've never read Lewis' "The Problem of Pain" you should pick it up. One of these days I am going to re-buy all my Lewis books that I've lent out over the years and have never had returned to me. I wish I still had my copy, because Lewis' insights in that book would compliment this thread.
(1)Diogenes Laertius, Lives of Eminent Philosophers, X, 22 (trans. C.D. Yonge).