“Omnipotence means ‘power to do all, or everything’. And we are told in Scripture that ‘with God all things are possible’.
“It is common enough, in argument with an unbeliever, to be told that God, if He existed and were good, would do this or that; and then, if we point out that the proposed action is impossible, to be met with the retort ‘But I thought God was supposed to be able to do anything’.
“This raises the whole question of impossibility.
“In ordinary usage the word ‘impossible’ generally implies a suppressed clause beginning with the word ‘unless’.
“Thus it is impossible for me to see the street from where I sit writing at this moment; that is, it is impossible to see the street ‘unless’ I go up to the top floor where I shall be high enough to overlook the intervening building.
“If I had broken my leg I should say ‘But it is impossible to go up to the top floor’–meaning, however, that it is impossible ‘unless’ some friends turn up who will carry me.
“Now let us advance to a different plane of impossibility, by saying, ‘It is, at any rate, impossible to see the street ‘so long as’ I remain where I am and the intervening building remains where it is’.
“Someone might add ‘unless the nature of space, or of vision, were different from what it is’.
“I do not know what the best philosophers and scientists would say to this, but I should have to reply ‘I don’t know whether space and vision ‘could possibly’ have been of such a nature as you suggest’.
“Now it is clear that the words ‘could possibly’ here refer to some absolute kind of possibility or impossibility which is different from the relative impossibilities and impossibilities we have been considering.
“I cannot say whether seeing round corners is, in this new sense, possible or not, because I do not know whether it is self-contradictory or not. But I know very well that if it is self-contradictory it is absolutely impossible.
“The absolutely impossible may also be called the intrinsically impossible because it carries its impossibility within itself, instead of borrowing it from other impossibilities which in their turn depend upon others. It has no ‘unless’ clause attached to it. It is impossible under all conditions and in all worlds and for all agents.
” ‘All agents’ here includes God Himself. 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 them with the two other words ‘God can’.
“It remains true that all ‘things’ are possible with God: the intrinsic impossibilities are not things but nonentities.
“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.”
— C. S. Lewis, The Problem of Pain, Chapter 2 (“Divine Omnipotence”), 1940.
