Calumny... gives [Harry] a spiritual purity in the sense that it scours away any outward show, any wish to live by the impression he makes on others. It gives him a lonely independence, so that he is able to act from his own depth. As he goes on to fulfill "his true destiny", which as far as he knows is his death, he is able to walk, hidden from view, past the woman he loves, without speaking, without looking back. This ability to act alone contrasts him with Voldemort, who needs others. That need is apparent in Voldemort's possession of Quirrell.
Voldemort's shallowness is apparent in the way Pettigrew has to do his work for him and then has to carry him to his rebirthing. Above all, it is in his need to be encircled by Death Eaters. Yet Voldemort is not truly in relationship with any of these people. He is connected to them only by magic, manipulation and threats. To be truly in relation with others, he would need, like Harry, to be capable of acting from his own depth. He would need to be able to act WITHOUT them. Voldemort, who wants to be independent, cannot truly act alone. ... Voldemort lives outwardly, in his domination of others; Harry lives inwardly, in the purity of his own being.
— Luke Bell
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