In a C. S. Lewis seminar class many years ago, I read, for the first time, Lewis’ sermon, “The Weight of Glory,” where my sense of longing for another place 
became the foundation for how I now live: not to be so enamored with the shadows of this world as to forget the reality of our hope. Lewis will use this to set our hearts for evangelism because if eternity is reality, then we are dealing with folks who are destined for a place: eternity in paradise in the presence of our maker or forever in a nightmare, doomed without any prospect of redemption.
Lewis brilliantly set up his hearers by stirring our sense of longing for another place: “We are half-hearted creatures, fooling about with drink and sex and ambition when infinite joy is offered us, like an ignorant child who wants to go on making mud pies in a slum because he cannot imagine what is meant by the offer of a holiday at the sea. We are far too easily pleased.” In fact Lewis points out that our desire for the promises of reward is not too strong but too weak.
The don is not satisfied to leave his sermon at that, but squeezes the point home, asking the question about our neighbor: “It may be possible for each to think too much of his own potential glory hereafter; it is hardly possible for him to think too often or too deeply about that of his neighbour [sic]. . . . It is a serious thing to live in a society of possible gods and goddesses, to remember that the dullest and most uninteresting person you can talk to may one day be a creature which, if you say it now, you would be strongly tempted to worship, or else a horror and a corruption such as you now meet, if at all, only in a nightmare.”
Then, with what I believe to be some of the greatest lines in Christian literature, Lewis closes out the sermon with this: “All day long we are, in some degree, helping each other to one or other of these destination. It is in the light of these overwhelming possibilities, it is with the awe and the circumspection proper to them, that we should conduct all our dealings with one another, all friendships, all loves, all play, all politics. There are no ordinary people. You have never talked to a mere mortal. Nations, cultures, arts, civilisations – these are mortal, and their life is ours as the life of a gnat. But it is immortals whom we joke with, work with, marry, snub, and exploit – immortal horrors or everlasting splendours.“
Lewis brilliantly forces us to see people for who they really are and gives us an impetus for gospel proclamation. May the Lord grant us the vision to see things as they really are.
