It is hard to fathom how "sharp" C. S. Lewis was...in his fiction as well as his non-fiction stuff. This of irritable, painful, yucky people in your life and carefully read on:
"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 neighbor.
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 talk to may one day be a creature which, if you saw 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.
All day long we are, in some degree, helping each other to one or other of these destinations.
It is in the light of these overwhelming possibilities, it is with the awe and 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, civilization--these are mortal, and their life is to 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 splendors.
This does not mean that we are to be perpetually solemn. We must play. But our merriment must be of that kind (and it is, in fact, the merriest kind) which exists between people who have, from the outset, taken each other seriously--no flippancy, no superiority, no presumption.
And our charity must be real and costly love, with deep feeling for the sins in spite of which we love the sinner--no mere tolerance or indulgence which parodies love as flippancy parodies merriment."
"The Weight of Glory," in The Weight of Glory (Eerdmans, 1949)