Hope is one of the Theological virtues. This means that a continual looking forward to the eternal world is not (as some modern people think) a form of escapism or wishful thinking, but one of the things a Christian is meant to do. It does not mean that we are to leave the present world as it is. If you read history you will find that the Christians who did most for the present world were just those who thought most of the next.
C. S. LewisDo not be deceived, Wormwood. Our cause is never more in danger than when a human, no longer desiring, but still intending, to do our Enemy's will, looks round upon a universe from which every trace of Him seems to have vanished, and asks why he has been forsaken, and still obeys.
C. S. LewisTelling us to obey instinct is like telling us to obey 'people.' People say different things: so do instincts. Our instincts are at war... Each instinct, if you listen to it, will claim to be gratified at the expense of the rest.
C. S. LewisNo more I do, your Majesty. But what's that got to do with it? I might as well die on a wild goose chase as die here.
C. S. LewisGod, who foresaw your tribulation, has specially armed you to go through it, not without pain but without stain.
C. S. Lewis