I have a friend who attended seminary with me but has long since stopped practicing his faith. He assured me that he is good with God. I asked if God is good with him, but I don’t believe he caught on to the difference, which is a very sad thing, because without that insight, he is heading for a very rude eternal awakening. In the stupendous article, “The Weight of Glory," C.S. Lewis says that this latter insight makes all the difference.
“How God thinks of us is not only more important, but infinitely more important. Indeed, how we think of Him is of no importance except in so far as it is related to how He thinks of us. It is written that we shall “stand before” Him, shall appear, shall be inspected. The promise of glory is the promise, almost incredible and only possible by the work of Christ, that some of us, that any of us who really chooses, shall actually survive that examination, shall find approval, shall please God. To please God . . . to be a real ingredient in the divine happiness . . . to be loved by God, not merely pitied, but delighted in as an artist delights in his work or a father in a son—it seems impossible, a weight or burden of glory which our thoughts can hardly sustain. But so it is.” 
The “weight of glory” Mr. Lewis refers, of course, is from St. Paul’s passage to the Corinthians:
“Therefore we do not lose heart. Though outwardly we are wasting away, yet inwardly we are being renewed day by day. For our light and momentary troubles are achieving for us an eternal glory that far outweighs them all. So we fix our eyes not on what is seen, but on what is unseen, since what is seen is temporary, but what is unseen is eternal” (2 Cor 4:16-18).
So, what is this weight, what is glory, and why is all of this so important? I admit it took the better part of yesterday afternoon to think through Lewis’ ideas, link them to Aquinas’ theology, and come out with something that make a good deal of sense, an insight with respect to our destiny which is heaven, an understanding that is essential in arriving there. (I hasten to add that if you see me writing for my own glory, run away as far and fast as you can.)
For Lewis, as for us, glory means two things. It signifies first a good report. Glory is the reward we receive for good works. It is a kind of renown from others, like getting an A on your report card. Glory is a good thing, something we want, but how we go about getting it makes all the difference. According to St. Thomas, we are only truly virtuous when we seek glory for the sake of God. Seeking “empty pleasure in human praise” is, on the other hand, vainglory. The distinction between true glory and false glory is that false glory seeks praise for its own sake, while true glory is sought, not for one’s own sake, but for God’s. 
Lewis expounds in his own words:
“Perhaps it seems rather crude to describe glory as the fact of being ‘noticed’ by God. But this is almost the language of the New Testament. St. Paul promises to those who love God not, as we should expect, that they will know Him, but that they will be known by Him (1 Cor 8:3). It is a strange promise. Does not God know all things at all times? But it is dreadfully re-echoed in another passage of the New Testament. There we are warned that it may happen to any one of us to appear at last before the face of God and hear only the appalling words: “I never knew you. Depart from Me.” In some sense, as dark to the intellect as it is unendurable to the feelings, we can be both banished from the presence of Him who is present everywhere and erased from the knowledge of Him who knows all. We can be left utterly and absolutely outside—repelled, exiled, estranged, finally and unspeakably ignored. On the other hand, we can be called in, welcomed, received, acknowledged. We walk every day on the razor edge between these two incredible possibilities.”
Hopefully, the distinction I made to my friend is now more obvious to all. To be known by God, or to have God good with you, is far more important than to imagine (else how would one “know”?) that you are good with God. The first is objective, absolute and assuredly real; the second is mere opinion, ephemeral, and quite possibly mistaken.
The second sense of glory, Lewis explains, is that of light, luminosity, brilliance; “we are to shine as the sun.”
“At present we are on the outside of the world, the wrong side of the door. We discern the freshness and purity of morning, but they do not make us fresh and pure. We cannot mingle with the splendours we see. But all the leaves of the New Testament are rustling with the rumour that it will not always be so. Some day, God willing, we shall get in. When human souls have become as perfect in voluntary obedience as the inanimate creation is in its lifeless obedience, then they will put on its glory, or rather that greater glory of which Nature is only the first sketch. For you must not think that I am putting forward any heathen fancy of being absorbed into Nature. Nature is mortal; we shall outlive her. When all the suns and nebulae have passed away, each one of you will still be alive. Nature is only the image, the symbol; but it is the symbol Scripture invites me to use. We are summoned to pass in through Nature, beyond her, into that splendour which she fitfully reflects."
What a lovely thought: nature is the first sketch of who we are. The implied second sketch is a coloring, perhaps, or a fuller rendition of who we are in our spiritual nature, reborn in Christ Jesus, adopted children of God. The brightness that we are burdened with is our opportunity in life to shine, to reflect the brilliance of God, to walk away with a good report, to be welcomed with the words:
“Well done, good and trustworthy servant! Since you've been trustworthy with a small amount, I'll put you in charge of a large amount. Come and share your master's joy!” (Mt 25:23)
But tomorrow comes and we carry our crosses, Lewis concludes, so what is the point of contemplating all of this? And here, his thoughts form into a perfect insight, namely charity:
“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. The load, or weight, or burden of my neighbour’s glory should be laid daily on my back, a load so heavy that only humility can carry it, and the backs of the proud will be broken. 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 the circumspection proper to them, that we should conduct all our 33 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, civilizations—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—no flippancy, no superiority, no presumption. And our charity must be a 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. Next to the Blessed Sacrament itself, your neighbour is the holiest object presented to your senses. If he is your Christian neighbour he is holy in almost the same way, for in him also Christ vere latitat—the glorifier and the glorified, Glory Himself, is truly hidden.”
What a spectacular conclusion! We mingle with potential saints or demons. There is no getting around it. The way we respond in charity to our neighbor will help make one outcome or the other real. And that is the weight of glory: that we carry one another’s crosses as well as our own, and we deliver redemption or death daily in the way we do so. I can think of little that is more significant for living the Catholic faith in an exemplary way. Would that my former seminary friend would come to the same insights, for both our sake.
O Great and glorious God, have mercy on us as we set out to faithfully carry the glorious weight of love you place in our hearts for one another!
 https://www.fadedpage.com/books/20141033/html.php#c2. It may be interesting to note that this article is from a Canadian print of Lewis’ work, as here in the U.S., even after 80 years of publication, his article remains under copyright.
 St. Thomas Aquinas, Summa Theologica, Volume 2, Part 2, Question 132, Answer 1.