What follows are 10 sentences from C. S. Lewis’s book The Weight of Glory (HarperCollins, 1949), pages 45–46. These sentences are not written to parents, nor are they concerned specifically with the the fine art of parenting. And of course they have far-reaching implications for all of life. But for me the most frequent situations when these lines bubble up from my subconscious is when I’m thinking about my kids and parenting them well. So that’s where the title comes from. But enough of me.

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 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 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 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 splendours. 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.