We all seek for rewards. It is not bad to do so. However, it depends on what kind of reward one is seeking. Lewis talks about two rewards: ones that have no natural connection with the things you do to earn it, and ones that do. If one seeks for the ones that lack natural connection, like marrying for money and not for the sake of love, then one is nothing more than a mercenary.
Using another more complex example, Lewis explains how we try to aim for heaven; the ultimate reward. The author writes that just like a student we first aim to please, to obtain good grades, to avoid punishment… all extrinsic rewards. However at some point, the student comes to love what he is studying and begins to aim and long for the proper reward. The first step is to obey, and the second, to long, will come naturally.
Now, longing comes when we view beauty. But this beauty is not ‘in’ the goods but is expressed ‘through’ them. “But if mistaken for the thing itself they turn into dumb idols, breaking the heart of their worshippers.” Longing is a “desire which no natural happiness can satisfy.” The source of beauty, the original beauty comes from God. The only way to cure longing is by obtaining Glory.
Glory is interpreted in the human way as fame and luminosity. But glory is actually something much grander and humbler, than something as transient and arrogant as that.
The human fame is a “competitive passion,” something given by fellow humans; and human passions always die away. Glory is in reality “fame with God, approval, “appreciation” by God.” The long and painful longing that could never be satisfied by material goods, can only cease the moment God smiles and says “you have done well.” One must recall those younger days when being praised by someone one loves and admires brought feelings of supreme bliss. Only a dependent child of God can enter paradise.
Luminosity is to shine. But we are not light bulbs trying to stand out from other light bulbs. We are humans, made in image of God himself. Our shine should not be one motivated by competition but one full of joy for obtaining glory. If we become perfect in “voluntary obedience”, we are bound to “outlive” nature, shine brighter than the morning star, and reunite with God.
However there is one more hurdle before one accomplishes all what is mentioned above. “The cross comes before the crown.” There is to be hard times before Glory. One must carry the neighbor’s weight of Glory, which is a heavy one, before achieving one’s own. It’s difficult without a strong will, and impossible without humility. The neighbors are also sons and daughters of God, not “mere mortals,” and one is to respect them, love them and with them, pursue Glory which is Christ himself.