If you can grasp this, you’ll get a great deal of what I have been trying to say about Heaven and Hell, free will, eternity, time, and knowledge of the divine.
From The Great Divorce, by CS Lewis (italics mine)
All answers deceive. If ye put the question from within Time and are asking about possibilities, the answer is certain. The choice of ways is before you. Neither is closed. Any man may choose eternal death. Those who choose it will have it. But if ye are trying to leap on into eternity, if ye are trying to see the final state of all things as it will be (for so ye must speak) when there are no more possibilities left but only the Real, then ye ask what cannot be answered to mortal ears. Time is the very lens through which ye see – small and clear, as men see through the wrong end of a telescope – something that would otherwise be too big for ye to see at all. That thing is Freedom: the gift whereby ye most resemble your Maker and are yourselves parts of eternal reality. But ye can see it only through the lens of Time, in a little clear picture, through the inverted telescope. It is a picture of moments following one another and yourself in each moment making some choice that might have been otherwise. Neither the temporal succession nor the phantom of what ye might have chosen and didn’t is itself Freedom. They are a lens. The picture is a symbol: but it’s truer than any philosophical theorem (or, perhaps, than any mystic’s vision) that claims to go behind it. For every attempt to see the shape of eternity except through the lens of Time destroys your knowledge of Freedom. Witness the doctrine of Predestination which shows (truly enough) that eternal reality is not waiting for a future in which to be real; but at the price of removing Freedom which is the deeper truth of the two. And wouldn’t Universalism do the same? Ye cannot know eternal reality by a definition. Time itself, and all acts and events that fill Time, are the definition, and it must be lived. The Lord said we were gods. How long could ye bear to look (without Time’s lens) on the greatness of your own soul and the eternal reality of her choice?