From Tolkien’s Requiem:
Melkor wants to possess the jewels in such a way that prevents others from possessing them. This is Melkor’s chief flaw from before the foundations of Arda: for him, love means possession and domination, the need to hoard and to guard a treasure as one’s own. In fact, in “Ainulindalë”, we learn that Melkor seeks to increase his own power and glory when he is already the most powerful and glorious of created beings. It seems that his own greatness leaves him jealous of the potential of others, with a need to see others always as a threat to his own glory. Thus, he must possess the Silmarils lest someone else do the same instead of him.
In truth, however, Melkor is not the only one to have such a possessive reaction to the Silmarils. Of Fëanor, Tolkien says that he “began to love the Silmarils with a greedy love, and grudged the sight of them to all save to his father and his seven sons; he seldom remembered now that the light within them was not his own” (69). Thus Fëanor is slowly corrupted by an illicit desire of possession. The light of the Silmarils, taken as it is from the Two Trees, is a light belonging to no individual or group of individuals but common to all. It is quite literally a light that fills the world. When Fëanor creates the Silmarils, he captures and contains something previously free to all. Though Melkor is the first to explicitly desire the Silmarils for his own, Fëanor and others soon follow suit. Thus, Fëanor’s love for the light of the Two Trees poisons the light by containing it, by making it scarce, when all along it is something that should not be contained. His desire and action to possess the blessed light sets into the hearts of the story’s free agents the will to possess it singularly and selfishly.
Ungoliant is an enigma and no easy read. Whereas from the beginning of the mythology Melkor is a vainglorious figure obsessed with domination, Ungoliant, on the other hand, is a mysterious figure of unknown origin, once corrupted to darkness by the seductions of Melkor, but having since repudiated his service for her independence. Yet despite her independence from Melkor, she hates the peoples of Valinor all the same. As Tolkien puts it, she is a figure “desiring to be mistress of her own lust, taking all things to herself to feed her emptiness” (73). Still, Melkor knows her deepest need, a desire to be filled by all things. He finds her in the dark caves to the south of Valinor, desperately hungry for the light of the Two Trees but hating it all the same, fearful of it and of the Valar who tend it (73). When he promises her fullness of the Light, she sets forth to do his bidding. Melkor wounds the trees, “and their sap poured forth as it were their blood, and was spilled upon the ground,” presenting Ungoliant with her feast (76). She sucks up every last drop of the Trees’ light-blood, bloating to a prodigious size, yet famished evermore. Ungoliant’s love is turned inward, seeking always fullness, but unable to find it. Acting alone, she is a poison to herself only; under the influence of another, she is a poison to many.
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