Religion involves a series of statements about facts, which must be either true or false. If they are true, one set of conclusions will follow about the right sailing of the human fleet: if they are false, quite a different set. For example, let us go back to the man who says that a thing cannot be wrong unless it hurts some other human being. He quite understands that he must not damage the other ships in the convoy, but he honestly thinks that what he does to his own ship is simply his own business. But does it not make a great difference whether his ship is his own property or not? Does it not make a great difference whether I am, so to speak, the landlord of my own mind and body, or only a tenant, responsible to the real landlord? If somebody else made me, for his own purposes, then I shall have a lot of duties which I should not have if I simply belonged to myself.…

Christianity asserts that every individual human being is going to live for ever, and this must be either true or false. Now there are a good many things which would not be worth bothering about if I were going to live only seventy years, but which I had better bother about very seriously if I am going to live for ever. Perhaps my bad temper or my jealousy are gradually getting worse—so gradually that the increase in seventy years will not be very noticeable. But it might be absolute hell in a million years: in fact, if Christianity is true, Hell is the precisely correct technical term for what it would be.

C.S. Lewis, Mere Christianity, bk 3, ch. 1